Multiple drops in Service - Lots of T3 and T4 Timeouts

We need to see the signal status numbers as well. Please also post the *Downstream Power Level*, the *Upstream Power Level*, and the *SNR* (Signal to Noise Ratio) numbers as well.

The signal stats are good but the error log entries indicate that something is going on. Perhaps there is noise ingress into the line(s) somewhere.

There are other signal stat figures that can't be read by the modem. They are the "Upstream Rx Power" (Upstream Receive Power Level), the "Upstream SNR Ch." (Upstream Signal To Noise Ratio), and the "Upstream ICFR" (In Channel Frequency Response). These are as equally important in diagnosing connectivity issues as are the modem's stats.

I'm going to escalate your issue to the Comcast corporate employees that are available to these boards. They will be able to poll the CMTS to see whether or not everything is in the green zone, see your node / cable plant and modem health, and also see a history plot for the modem. You should get a reply here in your topic. Good luck !

Awesome - Thank you

Greetings, @gclubhouse! I appreciate you taking the time to reach out to us here on the forums. I hope you are having an amazing day! I apologize to hear of the issues you are having with your internet dropping out. I work from home myself and certainly understand the need for a reliable connection. I would like to have a closer look at this and see what we can do to get this resolved for you. Can you please send me a PM with your first and last name so I may further assist you?

To send a private message, please click my name "ComcastMichael" then select "Send a Message" on the right side.

Hello,

Just stumbled upon this post and have this identical issue. Had techs come out multiple times, re-ran wires, and everything tested "Perfect" yet I'm unable to get above 250 MBPS in most cases and it fluctuates wildly all day. Can you help me Xfinity? Here are my logs. I feel like I'm getting ripped off paying for Gigbit when it can't barely get above 250 and then divebombs down to the 60s-70s (SOMETIMES TO KBPS!!!). Please help! Brand new Motorola MB8611 modem and TP-Link Deco M9 Mesh network. Thank you!

Event Log

Event Log          Time    Priority    Description      Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;     Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;     Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;     Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;     11:43:34 Sun Jul 4 2021   Critical (3)   SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;     11:45:20 Sun Jul 4 2021   Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;     11:51:55 Sun Jul 4 2021   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;     11:52:01 Sun Jul 4 2021   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;     11:52:58 Sun Jul 4 2021   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;     11:54:13 Sun Jul 4 2021   Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;     Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;     Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;     Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;     Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;     Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;     Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;     Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;     Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;     Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;     Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;     Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;     Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;     20:12:07 Tue Jul 13 2021   Critical (3)   Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;     Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;     Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;     Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;     Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;     Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;     Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;     Time Not Established   Notice (6)   Honoring MDD; IP provisioning mode = IPv6     18:46:03 Mon Jul 19 2021   Notice (6)   DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;     18:46:26 Mon Jul 19 2021   Notice (6)   CM-STATUS message sent. Event Type Code: 24; Chan ID: 37; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 0.;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.1;