COX Cable:  Motorola Surfboard SB4200 periodically loses connection for several minutes

Hi guys--

I have had an older Motorola Surfboard SB4200 modem that has worked successfully for 3.5 years on Cox’s cable network.  In the past three months, it periodically loses connection for about 10 minutes.  This only happens once a week or so, therefore it’s not a huge problem (not to the point where I have called customer service).  It should be noted that I have never had a problem with the modem, and usually when I notice that the lights have gone out, I can usually simply unplug the modem, then plug it back in and it will start working.  Here are a series of logs that from the http://192.168.100.1/logs.html log:


060120235914      3-Critical      T5.0      SYNC Timing Synchronization failure - Loss of Sync
060120235911      3-Critical      H501.4      HFC: LOST TRC SYNC- trying to recover
060120235911      7-Information      H501.12      HFC: FEC LOCK recovery OK
060120235911      3-Critical      T5.0      SYNC Timing Synchronization failure - Loss of Sync

These four events are repeated throughout the log and then I usually receive something like this:

060121000132      2-Alert      T507.0      Received Async Error Range Failed
060121000132      3-Critical      R4.0      Received Response to Broadcast Maintenance Request, but no Unicast Maint
060121000132      3-Critical      H501.8      HFC: T4 Timer Expired


Once I unplug the modem and let the lights all reset, everything seems to work fine for several days.  This system is operational 24/7.

Lastly, here are the current values from the signal page (while it's working properly):

Downstream  Value
Frequency 117000000 Hz Locked
Signal to Noise Ratio 38 dB
Power Level -2 dBmV The Downstream Power Level reading is a snapshot taken at the time this page was requested. Please Reload/Refresh this Page for a new reading

Upstream  Value
Channel ID 3
Frequency 22000000 Hz Ranged

Power Level 43 dBmV

Thanks for any help that you can provide!

Bill