I've had my Cox internet for about 5 months now, and only in the last month has this issue appeared. Multiple times a day my internet connection will briefly drop out before reconnecting within about a minute. In between these disconnections I have no issues at all, but they've been happening in the 10s of times per day lately.
I tried resetting my router and modem, neither of which had any effect on how often I disconnect. I did ping testing on my router and had sub millisecond responses when I lose my connection, so my router isn't the issue. When I looked on the longs for my modem I noticed that there have been multiple errors that frequently repeat themselves:
MDD message timeout;
SYNC Timing Synchronization failure - Failed to acquire FEC framing;
Started Unicast Maintenance Ranging - No Response received - T3 time-out;
The MDD and SYNC messages always happen at the same time, but don't seem to be tied to the T3 time-outs. Both of these two sets of messages coincide with my disconnects. From what searching I've done, T3 timeouts seems to indicate that there's an upstream issue so here's my information on that.
Modem: Motorola SB6183
Upstream Bonded Channels
Channel | Lock Status | US Channel Type | Channel ID | Symbol Rate | Frequency | Power
1 Locked ATDMA 3 5120 Ksym/sec 28414000 Hz 43.7 dBmV
2 Locked ATDMA 1 2560 Ksym/sec 17154000 Hz 42.3 dBmV
3 Locked ATDMA 2 5120 Ksym/sec 21984000 Hz 42.3 dBmV
4 Locked ATDMA 4 5120 Ksym/sec 34844000 Hz 43.8 dBmV
As for cable splits - I have no idea, I live in a multi-unit apartment building. Any advice or help is appreciated, thanks for your time.