Modem resets itself once or twice every day

[kitty]

So I have a Motorola Surfboard 5101 that's being fed interwebs by Cox Communications (unfortunately.) The internet has been dropping once or twice a day for the last month or two. I called Cox tech support and they said that it's probably the modem shutting itself off.

So I checked the logs and I see "Received Response to Broadcast Maintenance Request, But no Unicast Maintenance o" and some Googling came up with "received response to broadcast maintenance request but no unicast maintenance opportunities received" as the full message.

Sure enough after the entry in the logs the modem reports that it is "shutting down and rebooting."

Does anyone know how this is caused and/or how it can be alleviated?

[Pyrion]

Bit late but better late than never. What's your downstream SNR/power level and upstream power level? Downstream SNR should be anywhere between 25dB and 55dB, downstream power level should be between -12dBmV and 12dBmV (closer to 0 is best) and upstream power level follows the same rule as downstream SNR (between 25dBmV and 55dBmV). Anything outside these margins and the modem will tend to continuously reboot itself (as signal/power level is either "too loud" or "not loud enough").

This doesn't necessarily mean the modem is defective, chances are, it's the line itself that's defective, and usually this is fixed by running a clean split off the main direct to the modem itself with new cable.

I'm running a SB5101 on Cox as well.

[kitty]

My signal levels are fine according to Google. I'm at my parents' place for Thanksgiving right now so I can't give you the exact numbers but the last time I checked they were pretty much optimal.

I tried changing out their 4 (5?) way splitter for my two-way splitter. It was good for a few days and then it reset again. I definitely think it got better but then a week or so later it reset about two or three times within a couple hours. Though it was raining that day so it may have effed with their signals.

I'm thinking it's a defective line but if my SNR and power levels are fine then I would think that indicates otherwise.