For the last 3 days I have been experieing random outtages of about 12 hours. I have had the modem for 3+ years without any issues.
I contacted customer service via chat and they said my modem model is no longer compatible and thats likely the problem. If thats the case I have a hard time understanding why its all of a sudden an issue. Can somesome at Comcast help? They suggested I call and schedule a tech to come out but I dont think the issue is my wiring since its worked great for years.
The upstream power is too high /out of spec. That can cause random disconnects, spontaneous re-booting of the modem, and speed and latency problems.
In a self troubleshooting 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 5-1002 MHz, bi-directional, and no gold colored garbage types like GE, RadioShack, RCA, Philips, Leviton, Magnavox, and Rocketfish from big box stores like Home Depot, Lowes, Target, Wal-Mart etc. Splitters should be swapped with known to be good / new ones to test
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.
Sorry, you got some bad info from the rep, your modem is still approved for use with Comcast. The confusion comes from the fact that that model as a rental is no longer being used. Your retail version is fine.
You'll probably want to get a tech out there and address your signal issues - it could be old or degraded wiring or something with Comcast's signal.
I've asked a Comcast employee to help you. You should expect a reply in this thread.
I can help get a tech out if you haven't had one scheduled. Please send me a private message by clicking on my name, "ComcastChe" then click private message me. In the body of this message please verify your first and last name, street address including city state and zip code, and the account number or phone number associated with your services.
If you reply while I'm off, I will reach out when I get back in the office. My working hours are Sunday-Thursday's 2:30-11 PM MST.