MB8611 connection regularly drops

Both the Downstream power and the upstream power levels are out of spec. 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, 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 !

Thanks! I measured the power levels coming into the house and those seemed ok(-1dBmV). I ended up disconnecting the splitter that feeds the different rooms in favor of direct wiring the room with the modem since we aren't using the other rooms anyway. That ended up with about -5 to -7 dBmV per downstream channel.

That's still on the low / weak side... What do the upstream power levels look like now ?

So the upstream is a tad on the high side but both should be o/k as long as they remain stable. The bottom line now is to live with it for a while and see if the problem returns.

Here are the desired signal values from the pinned Troubleshooting Tips topic at the top of this board;

Good luck with it !

Unfortunately the problem has been persistent again. Usually at least once every other day, sometimes multiple times per day. I tried a couple different modems and it's happening on them all. Sounds like I should try to get a technician to come out? Is there a quick way I can schedule this?

Just for reference, I did find that my signals are going outside the values you referenced occasionally. I wrote a script to monitor the values throughout the day for the last few days and created some charts. The vertical lines are times associated with a critical error log.

Downstream