Bought a Netgear CM1150V Cable Telephony Modem to accommodate my new Xfinity Gig Service on 8/26. Had lightning fast speed (945/48) for about 10 days until internet connectivity began to falter while streaming Xfinity TV on my tablet. Internet speed went down to ~1-5mbps/0 mbp. Rebooted and factory reset modem and router a million times. Xfinity tech was out 3 times and each time said line was all clear, no issues with others in my area. Xfinity even laid a new cable line from the node to my house. Still, same conncetivity problem. Brought it to the attention of Netgear. Downstream bonded channel power is between -1.1 and .8 dBmV and upload channel speeds are 47-48.5 dBmV. Event logs consistently show "critical" priority issues with messages: "Started Unicast Maintenance Ranging - No Response received - T3 time-out" or "16 consecutive T3 timeouts while trying to range on upstream channel 1" or "Unicast Maintenance Ranging attempted - No response - Retries exhausted." So Netgear sends me a replacement modem. While waiting for the replacement, I reinstall my Arris Surfboard SVG2482AC. Works fine with consistent internet. No problems. Netgear replacement CM1150V arrives, I call Xfinity to assist with installation this time. After an hour with tech on the line and several reboots, the modem is successfully installed. Two days later, I am back to where I was with my initial modem. I now have inconsistent, mediocre internet service. When it works, this modem is incredible, but when it is not, it is tortoise slow. If it gets worse, I will have an expensive paperweight in my office and will reinstall the Arris Surfboard with the hopes one day it will be fixed.
My point: I am convinced Xfinity and Netgear need to refine the interface between the physical product and the service because it clearly DOES NOT WORK, at least not consistently. I anticipate the day when a new firmware update will resolve this but it will take good faith cooperation between the two companies to fix these bugs. I am hardly alone here as I see the same issues with others in the Netgear and Xfinity community forums. Any input is welcome. Thanks.
Yesterday I tried to switch from an older Arris model to a brand new Arris SB6190 modem.
1) The first issue was "your mac id is incorrect". OK. I DO know how to read, but sent them a pic showing I had that ability.
2) Some MAC ids aren't in their db, apparently. This had to be sent to someone else to enter, so that took a bit
3) Took them 4 tries to get it provisioned. Really awful speeds.
4) Then Im told it requires a service call. Huh???
Im getting 5-10MB down and 8-10 up on the new modem. That's directly connected via ethernet.
They can't simply revert to my old modem, because they decided its "no longer supported", even though its maybe 3 years old. So Im stuck with that.
When I connect to the "XfinityWiFi" network, Im getting similar bandwidth as the modem.
There is obviously something upstream causing these issues. They need to just admit and own it, and fix the problem.