Momentary occasional pixelation of NBC (703)

Though there are several other threads regarding various pixelation issues, I am convinced our problem (involving a condo complex) requires its own thread. Nonetheless, excuse any repetition (and my long post):

Comcast employees on this forum have helped me in the past and I thank them for their assistance.

We live in the SF Bay Area where we have been Comcast customers for more than 20 years.

Our home is in a 35 year old condo complex with original coax wiring home runs from individual units to various garage closets that house the Comcast connections/demarcations from the outside. We have 5 buildings of four stories each.

About a decade ago, we did a major renovation of our unit and, fortunately, our local Comcast field tech supervisor at the time (now long gone from Comcast) arranged for a senior tech to assist with laying out a plan to replace the old coax within our condo unit with quad-shielded RG-6 (though we’d still have the old home runs to the garage RG-59) using a media box installed in our wall to join the old and new cables including any necessary splitters and a powered electric outlet just in case we should ever need to add an amplifier. (Note: if a Comcast employee can/will help me, I can send him/her a schematic of the layout which includes the wiring origins, splitters and terminations including our current 2 year old setup of XG1v4 Xfinity DVR with three hard-wired XID-P remote “anyroom” cable boxes, an XR-15 TV remote control and an Xb-6 Xfinity Gateway -1GB service [central high location in the Condo] using both CAT-6 Ethernet and separated dual band networks for various wifi device connections).

For the most part, everything works pretty good though wireless speeds at distances beyond 20 feet can slow down during heavy wifi traffic across our condo building (approx 75 units) and complex (5 buildings). The other big issue however is the recent appearance of occasional momentary pixelation on at least one local channel - specifically NBC - on all four televisions in the “anyroom” setup. I say “at least” because a few of our neighbors (who have Xfinity cable) have also seen the same pixelation on one or more local channels in the 700-720 range. If my memory serves me correctly, we had a similar pixelation issue quite a few years ago, which affected us and many neighbors. But, it did eventually go away, which leads me to believe it was definitely a Comcast issue.

Whenever I’ve had Comcast techs here at our condo in recent years (for install of the newer equipment and for a suspected problem with one XiD [which ended up being a bad or incompatible HDMI port on an older Panasonic plasma TV]), they’ve said the Signal Strength is fine to all boxes. But, they’ve never provided more specific info like the data I used to be able to display on my old RNG DVR. (I’ve read descriptions of how to get to those screen for the XG1v4 using an XR-15 remote. But, I’ve yet to find any post about how to get out of diagnostics when you’re done. So, I am hesitant to try and access those screens.

Though I have little knowledge of what that diagnostic data says, I have to believe it may be able to provide troubleshooting info about the NBC channels, which might help Xfinity phone tech support make an adjustment (if possible?) that corrects any bad specs. BUT, due to different info you get from one phone rep to another phone rep and even from one on-site tech to another on-site tech, I have zero idea of what any of those folks are capable of doing, have done (or will do), or even if they’re on top of the issue and/or fix it.

Yes, I’ve checked the connections including coax and HDMI cables, done cable box restarts and refreshes, etc. But, for the past few weeks (beginning of our “winter”) the sporadic momentary pixelation, at least on NBC (channel 703), pops up occasionally (which is more than the very very rare occurrences of the past).

So, can I get your help in connecting with someone (hopefully this can all be done remotely since I’m in my 70s and our county is still in “lockdown” for Covid) who can determine the performance of my boxes beyond “signal is okay” and “I’ll send a signal”while paying particular attention to NBC (and other local stations since I can’t remember seeing the issue on basic and premium non-local cable channels) AND then make any necessary spec adjustments- e.g., the associated frequencies. Of course, it would be extremely helpful if you could also confirm how to get into and out of the diagnostics info screens on the XG1v4 and let me know which information would be helpful to you (and me for my own learning).

Again, current occasional momentary incidents of NBC pixelation are on all four TVs. But nothing in my overall setup has changed for two years and none of “our” cable connections in the condo building’s Comcast closet (in the ground level garage) have been altered, disturbed or subjected to outdoor elements.

FWIW, I’ve posted a query on our condo complex’s NextDoor social media group an am awaiting more replies beyond a few so far who have said they “...have a similar local channels pixellation issue” (several have verified the NBC occurrence.” I’ll keep trying to get more neighbors’ input.

Thanks for any help you can provide!