NETGEAR is aware of a growing number of phone and online scams. To learn how to stay safe click here.
Forum Discussion
Solved
Need help with Netgear CM2000 and bad downstream power levels...
Hi everyone. I just got a Netgear CM2000 to go with my Xfinity 1.2 Gbps plan, but I'm only getting speeds in the 400-600 Mbps range. I wanted to use the CM2000 to replace an older CM1000 that was...
gleelick wrote:Hi everyone. I just got a Netgear CM2000 to go with my Xfinity 1.2 Gbps plan, but I'm only getting speeds in the 400-600 Mbps range.
I wanted to use the CM2000 to replace an older CM1000 that was getting 900 Mbps on average out of the same cable line, so I'm not really sure what happened.
When I check the modem's diagnostics, I see that the "downstream power level" is bad. Specifically:
- Downstream Status: Bad
- Downstream Power Level: Bad
- Downstream power is poor (17.2dBmV). The recommended level is between -10dBmV to 10dBmV.
I also get these errors in the event log:Mon Nov 21 16:34:51 2022 (Warning (5)) RNG-RSP CCAP Commanded Power in Excess of 6 dB Below the Value Corresponding to the Top of the DRW;CM-MAC=c8:9e:43:e6:7e:b0;CMTS-MAC=00:01:5c:a4:f4:5d;CM-QOS=1.1;CM-VER=3.1; Mon Nov 21 16:22:43 2022 (Notice (6)) DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=c8:9e:43:e6:7e:b0;CMTS-MAC=00:01:5c:a4:f4:5d;CM-QOS=1.1;CM-VER=3.1; Mon Nov 21 16:22:36 2022 (Notice (6)) TLV-11 - unrecognized OID;CM-MAC=c8:9e:43:e6:7e:b0;CMTS-MAC=00:01:5c:a4:f4:5d;CM-QOS=1.1;CM-VER=3.1; Time Not Established (Notice (6)) Honoring MDD; IP provisioning mode = IPv6 Time Not Established (Critical (3)) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=c8:9e:43:e6:7e:b0;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
When I call Xfinity, they say everything is working fine on their end. Netgear support hasn't been very helpful, either. The modem firmware is V8.01.02Your downstream power levels are way too high. The recommended range is between 7 dBmV and -7 dBmV. The ideal value is 0 dBmV. Reference this Netgear article here: https://kb.netgear.com/24311/Power-level-guidelines-for-a-NETGEAR-cable-modem-router .
Only an Xfinity line tech can resolve that issue.
Are you testing directly connected to the modem? What site are you testing on?
I use the Ookla speed test both wired and wireless.
These are the entries in the event log now, after another reset:
Time Priority Description Tue Nov 22 09:39:28 2022 (Notice (6)) DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=[REDACTED];CMTS-MAC=[REDACTED];CM-QOS=1.1;CM-VER=3.1; Tue Nov 22 09:39:21 2022 (Notice (6)) TLV-11 - unrecognized OID;CM-MAC=[REDACTED];CMTS-MAC=[REDACTED];CM-QOS=1.1;CM-VER=3.1; Time Not Established (Notice (6)) Honoring MDD; IP provisioning mode = IPv6 Time Not Established (Critical (3)) No Ranging Response received - T3 time-out;CM-MAC=[REDACTED];CMTS-MAC=[REDACTED];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=[REDACTED];CMTS-MAC=[REDACTED];CM-QOS=1.1;CM-VER=3.1; Time Not Established (Critical (3)) No Ranging Response received - T3 time-out;CM-MAC=[REDACTED];CMTS-MAC=[REDACTED];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=[REDACTED];CMTS-MAC=[REDACTED];CM-QOS=1.1;CM-VER=3.1; If you're using both, what router is it connected to?
What speeds do you get with a pc directly wired into the modem?
The CM2000 is connected to the Nighthawk XR500.
When I'm hardwired to the modem itself, highest I can get is 600-700 Mbps.
Well, the logs are still indicating line issues.
Got a screen snip of the cable connections page with the splitter in there?
Here is a PDF of the cable connections page