CM1100 T3/T4 Timeouts & High Upstream Power (54+ dBmV)

My NETGEAR CM1100 cable modem is experiencing frequent connection drops and packet loss.

Looking at my modem's diagnostic interface (192.168.100.1), the signal metrics and logs show severe line noise and instability:

• Upstream Power Levels: Maxed out between 51.5 dBmV and 54.5 dBmV across all 4 upstream channels.

• OFDM Channel Issues: Downstream OFDM Channel 193 is constantly flapping with Event Code 16 and 24 (DS profile assignment changes) due to poor SNR and millions of uncorrectable errors.

• Event Logs: Filled with recurring T3 timeouts, T4 timeouts, and SYNC Timing Synchronization failures.

The modem is connected directly to the primary coaxial wall feed with no splitters installed anywhere in the setup, and I have already replaced the coax jumper cable. Since these metrics indicate high upstream attenuation and RF signal noise on the incoming line or street tap, I need an Xfinity technician dispatched to inspect and balance the line at my drop.