Motorola MT8733 Randomly Reboots

Please also copy all of the text in its entirety of the *Downstream Power Levels*, the *SNR's* (Signal to Noise Ratios), and the *Upstream Power Level* numbers and paste them into your next post.

@EG  Thank you for your response.  Here is the information you requested.

The upstream power levels are too high to being out of spec. The downstream power is on the weak side as well. That can cause random disconnects, spontaneous re-booting of the modem, speed, packet loss, latency problems, and the un-bonding of channels.

In an effort to try to obtain better connectivity / more wiggle room, check to see if there are there any excess/unneeded coax cable splitters in the line leading to the modem that can be eliminated/re-configured. Any splitters that remain should be high quality and cable rated for 5-1000 MHz, bi-directional, and no gold colored garbage from Radio Shack, Home Depot, Target, etc. Splitters should be swapped with known to be good / new ones to test.

Also check the coax cable for any damage such as cuts, nicks, abrasions, kinks, sharp bends, etc.

If there aren't any unneeded splitters that can be eliminated and if your coax wiring setup can't be reconfigured so that there is a single two-way splitter connected directly off of the drop from the street / pole with one port feeding the modem and the other port feeding the rest of the house/equipment with additional splits as needed and you've checked all the wiring and fittings for integrity and tightness and refresh them by taking them apart then check for and clean off any corrosion / oxidation on the center wire and put them back together again, then perhaps it's best to book a tech visit to investigate and correct.

Good luck with it !

Could the picture below explain the reason for my lousy signals and power levels posted earlier?  This is the splitter that the Comcast Tech installed in Nov 2020, when I first moved in and established service here.   It is a 3-way balanced splitter, all -5.5dB.  One leg goes directly to the MT8733, and the other 2 go to TV boxes.  I've always thought that the one going directly to the modem was supposed to be a different dB level than those going to TVs.

They are already indicated to be marginal..

@f2bme 

If there is nothing more that can be done to improve the connection quality, then you'll need a tech visit as stated. 

Bear in mind that if the premises facing techs can not find or fix a problem at your home, it is they who are responsible for escalating it to their line / network / maintenance dept. techs. The problem may lie beyond your home in the local neighborhood infrastructure somewhere but it is their S.O.P. to start at the home. And if the problem is found to be on their side of the demarcation point, there will not be any charge.

Good luck !

My pleasure ! It's why I lurk ! 🙂

Okay, so just to circle back around to report on updates/current status.  I have not experienced any further unexpected disconnects or random reboots of the modem/router (Motorola MT8733).  My US/DS signals and pwr levels are still only marginal to out of spec, but for some strange reason, this is not causing any problems.  My Xfinity plan is 800Mbps down and 20Mbps up.  I am consistently getting (via wired connection) 930Mbps down and 24Mbps up.  So, at this point I have no validity to complain. 

After investigating a bit, I did figure out why the signals and pwr levels are screwy (see earlier post where I provided them).  I hooked the modem router up to a coax right off of the primary main splitter that enters my condo unit.  DS/US signals and pwr levels were just about perfect.  My office, where I normally keep the router, is in a back room, enabling me to connect my PC via ethernet.  The bad news (for me, of course) is that the poor signals and pwr levels I'm experiencing in the office area are due to the cabling within my condo unit (condo was built in the mid-1980's), and therefore, I don't believe there is anything I can do about it.   

Thanks for the update ! You wrote: My US/DS signals and pwr levels are still only marginal to out of spec, but for some strange reason, this is not causing any problems. 

Be advised that some makes / models of modems / chipsets are more tolerant of less than stellar signals / connection quality than are others.

You wrote:

Unless there is a special arrangement, the unit owner for the inside of their unit, and the condo management for the common areas are typically responsible for the repair and maintenance of internal wiring / hardware.

@EG very interesting. Thanks for this information and all your help!  I'll have to check in with the Condo Association.  I'm the unit owner for my unit, but there are 3 other units within this building.  When you get into wiring, plumbing, etc., inside of walls, you're actually between units.  So, I'll see what their rules and regulations state about those responsibilities.  Thanks again! 

You're quite welcome ! Good luck with it ! Please post back about how things go.

Hello, I am posting back as requested to update the situation with the Motorola MT8733 modem/router.  I am still experiencing random reboots, which occur about every 2 days.  Signal levels, etc. as posted earlier in this thread, are still about the same and I know they were borderline on being unacceptable.  I have sent a DM to Xfinity to request a tech visit to check my line signals. 

@dcf_atl 

Please create a new topic of your own here on this board detailing your issue. Thanks. The original poster has not returned. 6-month-old dead thread is now being closed.

For future reference, it is better to submit your own post as it creates a ticket to get help, and posting on an old thread can delay getting help.

Also, please re-post those error log entries there but you need to redact all of the CM MAC and the CMTS MAC addresses from them for your privacy. They are considered to be personal information. The posting of personally identifiable information is a violation of their forum guidelines. The forum bot will not allow your post to be seen publically. It flagged your post as "Private".

And what do the modem's signal stats look like ? 

Please copy all of the text in its entirety of the *Downstream Power Levels*, the *SNR's* (Signal to Noise Ratios), and the *Upstream Power Level* numbers and paste them into your next post.