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XG1V4 box HDMI handshake problem

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Contributor

Re: Frequent no signal xfinity box hdmi

You have to go and manually switch it off. However if you watch 4K Netflix it will automatically switch forcing you to turn it off to watch regular tv
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Frequent Visitor

Re: XG1V4 box HDMI handshake problem

That doesn’t fix the issue. Once it happens a restart of the x1 box is required in my experience. I added a HDMI switch box between my x1 and my soundbar and that fixed it. But I don’t know why...
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Frequent Visitor

Re: XG1V4 box HDMI handshake problem

Hello All,

Just chiming in. Thought it was my older LG TV. or maybe my newer Yamaha receiver. Must me the XG1V4 box. I have the same issue so in my situation switching TV off and back on always works.

Just my $.02
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Contributor

Re: XG1V4 box HDMI handshake problem

Ken,

 

Similar problem with handshake failing. Tried new cables, switched ports, and I'm on my 3rd X1 box. I can eventually get 4K content from the box, like the soccer and baseball games recently, but I have to switch my TV to HDMI 1.4 and then quickly back to HDMI 2.0 to make it work. Rebooting also works. Didn't know about the turning off UHD possible fix--will try that tonight. I have a Comcast tech coming out tomorrow to check levels.

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Frequent Visitor

Re: XG1V4 box HDMI handshake problem

My UHD works fine seemingly, it is the HDR setting (aka Ultra Deep Color, the > 8 bit color scheme) that freaks out.  Try turning off Ultra Deep Color on your TV and see if that helps.  

 

I feel like the our LG tv (which just updated again a few weeks back) stopped forcing the Comcast box to Ultra Deep Color (but it does force it on the NVIDIA Shield an Fire TV we have switched through the same port on the TV, so that is inconvenient if someone uses one of those gets forced to turn it on and then restarts later with the XG1v4) because the Comcast box will again require a reboot to watch.  

 

 

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Contributor

Re: XG1V4 box HDMI handshake problem

Tried the HDR OFF setting on my TV--a Westinghouse WD55UT4490--with no luck. I give. It's obviously a Xfinity X1 box problem, and since there's little 4K programming available, I just set the box to 1080P and will monitor this forum for any firmware updates. If there's a rare 4K sports match I want to see, my Roku can supply it. I canceled the tech appointment. It would just be a waste of time. 2160@30Hz works, but it's the handshake at 60Hz that the box can't sustain.

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Re: XG1V4 box HDMI handshake problem

Potential resolution for me....

My LG 77 C9 TV updated firmware three days ago, included improving the ARC/EARC connection. I'm of the opinion my particular handshake issue involved the handoff from STB to TV to soundbar. This TV is hdmi 2.1. Have had reliable, repeatable proper on-off since. Maybe it will last.
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New Poster

Re: XG1V4 box HDMI handshake problem

I'm having the handshake problem. I go 4k box to Sony reciever to Sony TV. Sometimes everything works fine. Other times I get a black screen. Sometimes unplugging the power to the cable box will fix the issue but sometimes not. Sometimes unplugging the HDMI cable from the reciever and plugging it back in works but sometimes it doesn't. Sometimes I need to turn on my xbox so I get a picture then I can plug in the cable box and it works. This has been very frustrating. This has been going on for months for me.

 

-Matt

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Silver Problem Solver

Re: XG1V4 box HDMI handshake problem


@mmagikmatt wrote:

I'm having the handshake problem. I go 4k box to Sony reciever to Sony TV. Sometimes everything works fine. Other times I get a black screen. Sometimes unplugging the power to the cable box will fix the issue but sometimes not. Sometimes unplugging the HDMI cable from the reciever and plugging it back in works but sometimes it doesn't. Sometimes I need to turn on my xbox so I get a picture then I can plug in the cable box and it works. This has been very frustrating. This has been going on for months for me.

 

-Matt


Are the HDMI ports on the receiver and TV marked as CEC?


I am not a Comcast Employee.
I am just a customer, volunteering my time to help other customers here in the Forums.
Was your question answered? Mark the post as best answer!
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Valued Contributor

Re: XG1V4 box HDMI handshake problem


@mmagikmatt wrote:

I'm having the handshake problem. I go 4k box to Sony reciever to Sony TV.


Which Sony TV?  At least some of them will only accept 4k HDR @60hz on hdmi ports 2 and 3 and need to have the HDMI setting changed to 'enhanced'.   Also be sure your firmware is updated to the latest available.

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Frequent Visitor

Re: XG1V4 box HDMI handshake problem

I have an LG TV. Just got the new 4k box and all I get is a black screen. Ive been reading through this forum post and am shocked that this has yet to be resolved. None of these things you all do to fix it work for me. I literally just have a black screen.
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Re: XG1V4 box HDMI handshake problem

I was posting this under another thread. Had similar problems until about two weeks ago, when Comcast had a major outage in my area. No TV, phone or internet for about 4-5 hours. Ever since service was restored, I have not had a problem. Must be a software or signal strength problem on their end. Have a tech come out and show him this thread.

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Silver Problem Solver

Re: XG1V4 box HDMI handshake problem


@vikassi wrote:
I have an LG TV. Just got the new 4k box and all I get is a black screen. Ive been reading through this forum post and am shocked that this has yet to be resolved. None of these things you all do to fix it work for me. I literally just have a black screen.

Did you try all the LG HDMI ports?


I am not a Comcast Employee.
I am just a customer, volunteering my time to help other customers here in the Forums.
Was your question answered? Mark the post as best answer!
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Valued Contributor

Re: XG1V4 box HDMI handshake problem


@RobertWy wrote:

@vikassi wrote:
I have an LG TV. Just got the new 4k box and all I get is a black screen. Ive been reading through this forum post and am shocked that this has yet to be resolved. None of these things you all do to fix it work for me. I literally just have a black screen.

Did you try all the LG HDMI ports?


And are they set to ultra deep color or not?

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Re: XG1V4 box HDMI handshake problem


@lesmikesell wrote:

@RobertWy wrote:

@vikassi wrote:
I have an LG TV. Just got the new 4k box and all I get is a black screen. Ive been reading through this forum post and am shocked that this has yet to be resolved. None of these things you all do to fix it work for me. I literally just have a black screen.

Did you try all the LG HDMI ports?


And are they set to ultra deep color or not?


I have a Pioneer VSX-60 receiver, so my cable box is plugged into that and then the TV out goes to the TV, from the receiver.  Very typical setup.  This new box just doesnt want to work, just a black screen.  It worked the first time i hoooked it up but now just a black screen.  Everyday.  I have done what a few other people have done here to fix it, but it ALWAYS happens again, the next day.  Unplugging the HDMI ports, power cycling the Xfinity box, etc. DO NOT fix the problem for me.  I literally have to plug the Xfinity box directly into the TV, power cycle the box, then it comes on, THEN, hook everything backup the way it was, to the receiver, etc, WITHOUT turn off ANYTHING, and then it works.  But that is a CRAZY workaround.  

 

I think it could have something to do with the Pioneer receiver, as its not a 4K / HDR receiver, but the cable box knows this and automatically sets the highest resolution to 1080.  It doesnt even give the option for 4k resolution.  I know there is some type of problem there as on the receiver, there is an HDMI light that goes on, once it recongnizes theres a device plugged into that input, that is HDMI.  At times, that light will flicker, turning on and off, indicating some type of hand shake problem.  Eventually, it will turn solid, indicating the cable box has signal, but it just shows a black screen.

 

I have tried the TV inputs to deep color and not deep color, nothing works.

 

When i was setting up the next box, it did give me a message saying there was a low signal from this output.  I called Comcast and reported this and get this, they wanted to CHARGE me $70 to come out to troubleshoot.  I almost just cancelled by service.  The worst customer experience i have ever had to date with Comcast, and i have had quite a few bad ones.

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Re: XG1V4 box HDMI handshake problem

Recently switched from Directv to Comcast. Had 0 problems with DTV for almost 20 years.

Got 2 xFinity boxes. Nothing but issues so far.

My set-up

1 DVR in Family Room, 1 smaller non-DVR box in basement.

basement box when powering on, the TV will show no signal. Replaced the HDMI cable. No help. Moved HDMI to different TV port. No help. Change TV HDMI ports to 2 and back to 1, no help.

The ONLY way I can fix it is pull the power on the box and let it reboot. Works perfect after that.

Watch TV, power the sytem off. Come back the next day - same issue.

 

This is so frustrating and a complete waste of our time.

I have read ll of the comments, and it seems like there is no fix.

Anyone know how to fix this issue?

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Contributor

Re: XG1V4 box HDMI handshake problem

Does your basement box have its own tuner?We had similar issue until they changed the box to one with its own tuner - bigger box,  but problem free ever since

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Re: XG1V4 box HDMI handshake problem

Yes, it has its own tuner, remote, etc. Once I reboot it works fine until I turn it off and back on a few days later. Then I need to reboot it again.

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Re: XG1V4 box HDMI handshake problem

On the LG C8 (at least), only HDMI 2 supports ARC.  So if you are using a X1 <=> AV RCVR <=> TV and want to use any type of SMART tv functionality (like Netflix, Amazon, etc) then you need to pull the audio back via ARC over port 2 so that you get audio on from the TV on those apps.

 

I just got a Yamaha and an LG update and the problem seemed to disappear for a couple of days, but yesterday - BLACK screen again.  This time however, pulling and re-inserting the HDMI cable at the X1 terminal restored it.  I'll try to turn off the energy saver again and see if that helps.

 

Would be nice if Comcast test lab would start to duplicate these issues and drive resolution with their own groups or vendors.  1+ years is a long time...

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Re: XG1V4 box HDMI handshake problem

I got another bug fix from xfinity but still after all this time the issue does not seem to be addressed
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Contributor

Re: XG1V4 box HDMI handshake problem

3 weeks ago, get up in the morning turn on tv, starts flashing from black screen to the picture, about a flash every second, and it does this for 10 minutes roughly before the picture locks in.  or, i can unplug the box, plug it back in, wait for the boot up and the picture comes right in after only a few minutes, and is good from that point on, unless i turn the tv off for a lengthy period of time, over an hour or more, then the same problem.

i had comcast swap out the old box for a new one, still have the problem.  tv is lg, makes no difference unplugging and plugging back in the hdmi cable.

really frustrating having to unplug the box every morning, or just sitting there for 9 minutes and waiting for the flashing back and forth to stop.

come on comcast, too many of us have this problem, and there has got to be a fix on your end.

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Valued Contributor

Re: XG1V4 box HDMI handshake problem

Some posts have said that turning ultra deep color off for the port has fixed it for some LG models.

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Re: XG1V4 box HDMI handshake problem

I've been dealing with since NOVEMBER 2018 YES 2018. Turning off UHD to the box port fixed it.  Made no difference in quality of any content SUPPLIED via  X1 Box   Thanks to those that told me MANY months ago to turn off UHD  to that port. 

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Valued Contributor

Re: XG1V4 box HDMI handshake problem

I'm curious about what that setting really does.   Maybe it expects 12-bit DolbyVision HDR color continuously as a device like the Apple TV might deliver.     The xg1v4 only does standard 10-bit HDR and only when the content provides it.

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Re: XG1V4 box HDMI handshake problem

i don't have 4k, don't have a uhd to turn on or off.

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Valued Contributor

Re: XG1V4 box HDMI handshake problem

Does it make a difference if you lock the xg1v4 output to 720p?

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Re: XG1V4 box HDMI handshake problem

i'll have to change it to 720p tonight before i  shut the tv off, then in the mornin when i turn the unit back on see what happens?  but if it only works  on 720p, what's the sense?

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Valued Contributor

Re: XG1V4 box HDMI handshake problem

I thought you said you didn't have a 4k TV.   So 720p is the best resolution for many/most things (for reasons too complicated to explain here - look up why it is used for sports broadcasts).  Even if you do have a 4k TV unless you are watching 4K content your expensive TV can generally upscale as well as the X1 box.    Xfinity only has a tiny amout of 4k programming (updated regularly here: https://www.xfinity.com/support/articles/uhd-4k-faqs) along with the Amazon/Netflix apps that are also probably available on your TV or other devices you own.

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Contributor

Re: XG1V4 box HDMI handshake problem

Right, i don't have a 4k tv.  it's LG, has 480p, 720p, 1080i, and 1080p options, and the x1 box automatically chooses: (as shown on the video output resolution) "1080p60hd (best available)"

i know the the x1 will upscale, by why make the box/tv upscale, when there are settings to choose that set the scale?  or, that the box finds and sets as "best available?"

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Valued Contributor

Re: XG1V4 box HDMI handshake problem

Apparently your TV is offering a 'best available' that doesn't actually work.   Otherwise you wouldn't be having problems.   I'm suggesting trying something that might work.   And since most of the content from Xfinity is delivered at 720p, won't harm what you see.    Your local broadcast channels might be carried at 1080i but 1080p60 is something just made up by the box - which would be OK if the TV accepted it, but not really an improvement and not worth dealing with problems over.

 

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Re: XG1V4 box HDMI handshake problem

as i said yesterday, "set the tv to 720p last night before turning the tv off for the night.  turned it on this morning and same flashing in and out for about 8 minutes before the picture locked.

i didn't think it would make much difference.  i have been comcast customer for 16 years, have never had an issue, have never had a connection issue, until about 3 weeks ago when this all started.  nothing different in the equation, other than the problem.

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Valued Contributor

Re: XG1V4 box HDMI handshake problem

That is sounding more like a problem with the TV.  Have you tried a different HDMI port?

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Re: XG1V4 box HDMI handshake problem

tv is wall mounted, only way to to check current hdmi cable at tv is to have someone remove tv from wall mount so that connection can be checked, but so no reason why the connection would all of a sudden change when nothing behind the tv has been touched/changed?

as to trying a different hdmi, i got to run to the store, pick one up, wait till tonight when i'm shutting down, turn tv off, unplug hdmi from box, plug new cable in to box and then to hdmi on side of flat screen.  and then wait till morning and turn set on and see what i get.  more then..thanxz so far for the conversation, regardless...lol

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Valued Contributor

Re: XG1V4 box HDMI handshake problem

I've had the HDMI ports go out on a TV - it happens.  I was able to continue using it for a while with component cables but eventually replaced it.

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Re: XG1V4 box HDMI handshake problem

but isn't it strange that every morning there's this problem, for about 8 minutes, then the picture locks in.  no problems the rest of the day.  have turned the tv off for short periods, 30/45mins to an hour, no problem when turning baack on.  have shut it off for over 2 hours and no problem turning back on, picture instantly.  turn it off over night, back on in morning, same problem.

so will try the new cable in the morning.  hopes it not the hdmi, will have to call someone in to change it out for me.

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Re: XG1V4 box HDMI handshake problem

Why don’t you change the subject of your posts. This is not a handshake issue which is what this thread was about.
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Re: XG1V4 box HDMI handshake problem

i would hope that it's not a  handshake problem, and a simple hdmi cable or port, but if my post isn't a handshake problem, then others in this thread aren't either i guess?  how did you come to this conclussion, just curious?

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Valued Contributor

Re: XG1V4 box HDMI handshake problem

Real handshake problems would never display anything.  Most of the posts here are about having 4k settings and failing to display when the TV and/or X1 box have been in sleep/low power mode and have different timing as they wake up.  Generally they are OK if you power cycle one or the other or both, or just disconnect/reconnect the HDMI cable, or simulate that by switching the TV input to another port and back.  Some have found a permanent solution, some haven't.

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Re: XG1V4 box HDMI handshake problem

Thanks for explaining the point of this thread!
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Re: XG1V4 box HDMI handshake problem

brand new hdmi cable, plugged in to different hdmi port...............same problem, 9 minutes of flashing from black screen to picture, to black to picture every second, for 9 minutes.  so, what's the next guess?  hdmi motherboard ?  new oled tv on the horizon..............

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Valued Contributor

Re: XG1V4 box HDMI handshake problem

Considering the cost of repairing anything these days and the sale prices of new TV's, I'd go for new.  But, you might want to try swapping the X1 box first or maybe even finding one of the old versions that has component output.

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Re: XG1V4 box HDMI handshake problem

refresher:  a little over 3 weeks ago, turning on the tv the first time in the morning, the problem started.  9 minutes of the flashing from black screen to the broadcast picture, flashing back and forth every second, for 9 minutes.  then the picture would lock in, and no problem for the rest of the day, even after turning the tv off at various times during the day, then back on when we got home or wanted to watch tv, no flashing, instant broadcast picture.  the next day, when i turned on the tv and the flashing started, i unplugged the x1 box, waited 20 seconds, plugged it back in, tv showed the restart process, and when it was done and booted up i had my picture.

the 3rd morning when it did that, i unplugged the hdmi from the box, plugged it back in, no change, still flashing.  unplugged box, plugged back in, boot process, broadcast picture there.

 

had comcast out on 4th day, swapped box out for the new one, next morning turned on tv, flashing still there.  so not the box.  did some searching online for other's with same issue, came here, started reading.  finally decided to swap hdmi cable out, and try new hdmi port, which brings me to where i am this morning, and will be looking for a good deal on a samsung 65" oled.

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Valued Contributor

Re: XG1V4 box HDMI handshake problem

Getting pretty far off-topic here, but don't confuse Samsung's QLED with OLED.  They are both good but very different things.   QLED is about filtering the backlight to a pure-white color where OLED actually emits the colors directly instead of having a backlight and is completely off for pure black.

https://www.techradar.com/news/oled-vs-qled

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Re: XG1V4 box HDMI handshake problem

good article, thanks!  OLED sounds like the better way to go if high quality picture with high dollar price goes hand in hand.  QLED sounds like it's almost as good but at a lower price.

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Valued Contributor

Re: XG1V4 box HDMI handshake problem

OLEDs have better blacks and near-blacks - so they are probably the best for dark movie scenes in a dark room.  They may not have the brightness to compete with windows for watching TV in the daytime.  But really they are all pretty good these days.  This site has good reviews and comparisons.

https://www.rtings.com/

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Re: XG1V4 box HDMI handshake problem

Again, these comments are off subject. Start a new thread. Thanks
New Poster

Re: XG1V4 box HDMI handshake problem

Sony XBR here, encountering the same issue. Replaced the box with Xfinity, didn't change a thing. 

 

It's only a problem when using ARC - has anyone found a solution at all? This thread has been open for more than year. 

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Re: XG1V4 box HDMI handshake problem

The common denominator is Comcast/Xfinity not getting it fixed. The TV manufacturers need to work with all sources. Comcast does not care because they are not losing $ or customers.
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Valued Contributor

Re: XG1V4 box HDMI handshake problem


@Bish0p wrote:

Sony XBR here, encountering the same issue. Replaced the box with Xfinity, didn't change a thing. 

 

It's only a problem when using ARC - has anyone found a solution at all? This thread has been open for more than year. 


I think this is the first I've seen Sony mentioned with this.   Are you connecting the X1 to one of the HDMI ports that take 4k HDR (2 and 3 only on many models) and have the enhanced setting on?

 

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New Poster

Re: XG1V4 box HDMI handshake problem

Hello, 

I had this issue for the longest time. Went through multiple boxes with no change. Tried everyting that was described about settings and nothing changed. I finally found a solution that has worked for me for over the last 6 months and thought I would share, hopefully this will help some.

 

I found the issue had to deal with universal remotes. If I were to turn off and on the TV with the Xfinity remote I had no issues. I noticed it was only an issue with my TVs universal remote if I used to it turn the TV on or off. I have a Samsung TV with a universal remote and when the TV detects a new device on an input it automatically goes through and sets up the remote. You do have the option to skip the universal remote set up or remove it. Once I did this I have not had any issues with the black screen. Only downfall is you will not be able to use your TVs remote to control your cable box.