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eman970's avatar
eman970
Tutor
Apr 18, 2026

Have CM400 modem with upload slowdowns that happen at regular intervals

I have a CM400 modem and lately I have experienced a slowdown of only my upload speed starting at a specific time of day between 7:30pm and 8pm for the past week. My upload speed goes from 30mbps bef...
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eman970's avatar
eman970
Tutor
Apr 19, 2026

I'm having to post the event log in two parts as the system won't allow me to post it in 1. Here is the second half. Kep in mind my upload problems began around 4/12...

 

 

Apr 13 00:10:26 2026Warning (5)MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1
Apr 13 15:36:07 2026Critical (3)No Ranging Response received - T3 time-out
Apr 14 00:22:38 2026Warning (5)MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1
Apr 14 02:41:43 2026Critical (3)No Ranging Response received - T3 time-out
Apr 16 12:58:20 2026Critical (3)Unicast Ranging Received Abort Response - initializing MAC
Apr 16 12:58:20 2026Critical (3)No Ranging Response received - T3 time-out
Apr 16 12:59:16 2026Warning (5)MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1
Apr 16 12:59:19 2026Critical (3)No Ranging Response received - T3 time-out
Apr 17 09:35:36 2026Critical (3)SYNC Timing Synchronization failure - Loss of Sync
Apr 17 09:35:41 2026Warning (5)Lost MDD Timeout
Apr 17 09:36:25 2026Critical (3)Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out
Apr 17 09:49:55 2026Warning (5)MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1
Apr 17 22:02:38 2026Critical (3)SYNC Timing Synchronization failure - Loss of Sync
Apr 17 22:02:42 2026Warning (5)Lost MDD Timeout
Apr 17 22:03:31 2026Critical (3)Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out
Apr 17 22:04:46 2026Warning (5)MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1
Apr 17 22:04:49 2026Critical (3)No Ranging Response received - T3 time-out
Apr 17 22:05:46 2026Warning (5)Initializing Channel Timeout Expires - Time the CM can perform initial ranging on all upstream channels in the TCS has expired
Apr 17 22:05:47 2026Warning (5)TCS Partial Service
Apr 17 22:06:16 2026Critical (3)Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out
Apr 18 01:28:30 2026Critical (3)No Ranging Response received - T3 time-out
Apr 18 15:02:17 2026Warning (5)MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1
Apr 19 01:44:27 2026Critical (3)No Ranging Response received - T3 time-out