TV pixelation when running Internet Speed Test

[reswan01]

Hi. I am having and issue where the tx pixelates / freezes. This seems to only happen on a few channels 841, 842, 843. I contacted Comcast last week and was told the channels themselves were having issues and the network team would fix it. It has been good now for a week, but is back now. Whats weirder is that if I run the internet speed test from the xfi app on my phone, during the upload portion of the test, the pixelation is terrible. I can make the issue happen with the speed test. I have the 600 mps speed package.

[1gatir2knights]

I am having the same problems with TV pixelation and the sound freezing.Happens on every channel and has been going on for a couple of days now. Rebooted,refreshed,nothing works.

[Rustyben]

call 800-comcast so they can send a tech to determine the cause of low signal/high noise on some channel frequencies.

[reswan01]

We had a tech out 2 weeks ago. He went up the pole outside and removed a filter. It was ok after that for a week. Last week I was told that the issue was channel specific (on the broadcaster end) and that the network team was working on it. That cant be true if I can cause the tv pixelization issue to get immediately worse by running a speed test.

[Rustyben]

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@reswan01 wrote:
We had a tech out 2 weeks ago. He went up the pole outside and removed a filter. It was ok after that for a week. Last week I was told that the issue was channel specific (on the broadcaster end) and that the network team was working on it. That cant be true if I can cause the tv pixelization issue to get immediately worse by running a speed test.

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on a set top box or a roku or smart phone/tablet? 

[Rustyben]

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@reswan01 wrote:
We had a tech out 2 weeks ago. He went up the pole outside and removed a filter. It was ok after that for a week. Last week I was told that the issue was channel specific (on the broadcaster end) and that the network team was working on it. That cant be true if I can cause the tv pixelization issue to get immediately worse by running a speed test.

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you can check the same channel on a smart phone/tablet or a PC to see the very same network feed that comes to your home (numbered channels). if pixelated on both then that would prove the case, if not pixelated on the streaming device, then it is from comcast to the home or within the home wiring.

[reswan01]

Thanks for the reply. I streamed one of the channels on laptop at the same time as viewing the channel on tv. When the speed test is run, the tv pixelates then freezes until the speed test finishes. The laptop stream had no issues at all.

[Rustyben]

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@reswan01 wrote:
Thanks for the reply. I streamed one of the channels on laptop at the same time as viewing the channel on tv. When the speed test is run, the tv pixelates then freezes until the speed test finishes. The laptop stream had no issues at all.

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ok that isn't what I meant (I do apologize).  go to the set top box that has the pixellation problem. use the voice remote command 'about'. what is the rest of the line to the right of "STB Version"? I'm guessing it is an xi5 or xi6. if so, and it is connected via wifi the speed test will attempt to max out the 'home' to 'server' pipe which if your set top box is an xi5/6, it shares and will be starved for data during the test. What should be worked on is pixelation while no speed test is happening to figure out the problem.

[reswan01]

Stb version AX014AN_4.0p16s1_PROD_sey

[reswan01]

Hi. Thanks for the response. The issue isnt only happening when the speed test runs. It just makes it way worse. At night it is pretty much fine. During the day we now have 3 people working from home (covid situation) and when all are logged in to work, the 3 channels struggle.

[Rustyben]

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@reswan01 wrote:
Stb version AX014AN_4.0p16s1_PROD_sey

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that is a 4k DVR and it has its own tuners. an internet device should not have any affect on receiving the over the air channel frequencies the cable box uses (for numbered channels). when you play back a recording on that DVR and then press 'ok' button does the source show on the screen as DVR or 'cloud icon' DVR?

[reswan01]

It just shows DVR. (No cloud icon)

[Rustyben]

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@reswan01 wrote:
It just shows DVR. (No cloud icon)

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ok so the DVR's tuners are working (did not 'fall back'  to IP TV. The DVR should not even be aware of anything you are doing on the internet. some noise is getting into the TV line somewhere. a tech will have to locate the problem. you can remove and reinstall the exposed coax ends to be sure they are seated properly and hand tight. 

[reswan01]

Thanks. I have a tech coming Monday. I will provide an update.

[andyross]

Getting pixelation while running a speedtest from a modem is a sign your upstream is near maximum for your modem. I had a similar issue at my parents house a year or so ago. The modem was maxed out around 55dB or more.  It's screaming so loud that it's overloading the X1's tuner.

[reswan01]

Hi. Thanks for the reply. My modem is fairly new. Model CGM4140COM. Should I upgrade it (is there a newer version)?

[andyross]

The model of modem makes no difference. You need to go to the diagnostics for your modem and check the signal levels. Many places online with info on how to do that for various modems. Check the upstream levels. If they are going over 50, that can sometimes cause issues with other devices. Even though the frequencies are far apart, the signal strength can overload the tuner inputs and cause interference no matter what frequency that tuner is at.

[Rustyben]

adding ... the modem in the x1 set top box is completely separate and on different channels different CMTS (device the X1's modem connects to) etc. it should have no relation whatsoever to the customer modem and its channels used.

[reswan01]

I agree. It shouldnt, but yet its happening. Not only speed test, but uploaded a large video to my Amazon drive via laptop (wifi) and the tv channel completely broke up for the 5 mins it took to finish the upload. As soon as the upload hit 100%, channel was viewable again.

[CCAndrew]

Post the signal levels of your modem, upstream, downstream and SNR.

[reswan01]

I actually may have semi - solved the issue. The stb and the gateway are on the same wall jack with a splitter. Its behind the tv stand console. The cables from each branch of the split were touching each other and laying on the splitter. I separated rhe cables and got them off the splitter and havent had an issue since. Do you think one of the cables is bad? Possibly the coax plate in the wall?