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|018-2-26, 19:02:06||Critical (3)||SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=XX:XX:XX:XX;CMTS-MAC=XX:XX:XX:XX;CM-QOS=1.1;CM-VER=3.0;|
|2018-2-26, 19:02:12||Warning (5)||MDD message timeout;CM-MAC=XX:XX:XX:XX;CMTS-MAC=XX:XX:XX:XX;CM-QOS=1.1;CM-VER=3.0;|
|2018-2-26, 19:02:13||Critical (3)||SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=XX:XX:XX:XX;CMTS-MAC=XX:XX:XX:XX;CM-QOS=1.1;CM-VER=3.0;|
|2018-2-26, 19:04:13||Warning (5)||MDD message timeout;CM-MAC=dc:ef:09:7d:c4:30;CMTS-MAC=dc:eb:94:b5:3d:cc;CM-QOS=1.1;CM-VER=3.0;|
|2018-2-26, 19:04:20||Critical (3)||SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=XX:XX:XX:XXCMTS-MAC=XX:XX:XX:XX;CM-QOS=1.1;CM-VER=3.0;|
|2018-2-26, 19:04:24||Warning (5)||MDD message timeout;CM-MAC=XX:XX:XX:XX;CMTS-MAC=XX:XX:XX:XX;CM-QOS=1.1;CM-VER=3.0;|
I'm getting all of those error after reboot. I also have fw that is newer than Netgear has. Can anybody help?
I also get lots of unrecoverables. Last time I had this Comcast denied any issues, but then I saw multiple Comcast trucks by the cable box and it was fixed after that.
|Channel||Lock Status||Modulation||Channel ID||Frequency||Power||SNR||Correctables||Uncorrectables|
|1||Locked||QAM256||9||543000000 Hz||1 dBmV||40.1 dB||21313||6960|
|2||Locked||QAM256||13||567000000 Hz||1.4 dBmV||40.1 dB||3||0|
|3||Locked||QAM256||14||573000000 Hz||1.4 dBmV||40.1 dB||4||0|
|4||Locked||QAM256||15||579000000 Hz||1.2 dBmV||40.1 dB||67||330|
|5||Locked||QAM256||16||585000000 Hz||-1.1 dBmV||39.2 dB||20||0|
|6||Locked||QAM256||1||489000000 Hz||1.1 dBmV||40.7 dB||6||0|
|7||Locked||QAM256||2||495000000 Hz||1 dBmV||40.4 dB||10||0|
|8||Locked||QAM256||3||507000000 Hz||1.1 dBmV||39.6 dB||15||0|
|9||Locked||QAM256||4||513000000 Hz||0.8 dBmV||40.3 dB||12||0|
|10||Locked||QAM256||5||519000000 Hz||0.6 dBmV||40.1 dB||368||1707|
|11||Locked||QAM256||6||525000000 Hz||0.7 dBmV||40.1 dB||3390||14714|
|12||Locked||QAM256||7||531000000 Hz||0.7 dBmV||40.1 dB||21237||33380|
|13||Locked||QAM256||8||537000000 Hz||0.8 dBmV||40.1 dB||61412||27794|
|14||Locked||QAM256||10||549000000 Hz||1.2 dBmV||40.1 dB||34945||16773|
|15||Locked||QAM256||11||555000000 Hz||1.3 dBmV||40.1 dB||42644||17771|
|16||Locked||QAM256||12||561000000 Hz||1.3 dBmV||40 dB||3403||14028|
Depending on the total *uptime* of the modem, those *uncorrectable* bit errors may be quite low. The downstream signal stat figures are good. What do the upstream power level figures look like ? Are you actually experiencing any connectivity issues ?
Here is the upstream
|Channel||Lock Status||US Channel Type||Channel ID||Symbol Rate||Frequency||Power|
|1||Locked||ATDMA||1||5120 Ksym/sec||37800000 Hz||49.6 dBmV|
|2||Locked||ATDMA||2||5120 Ksym/sec||31400000 Hz||49.6 dBmV|
|3||Locked||ATDMA||3||5120 Ksym/sec||25000000 Hz||48.9 dBmV|
|4||Locked||ATDMA||4||5120 Ksym/sec||18600000 Hz||49 dBmV|
It seems I'm. I have 2 wifi routers. My setup is Netgear R7000 as the main router and Asus 68U as a media bridge. It seems that I'm experiencing internet drop-offs. I thought maybe R7000 is having issues so I re-configured 68U to be the main router, but I'm still having the same issues. btw fw on CM500 has changed from V1.01.08 to V1.01.09 in the last couple of months.
The upstream power is borderline / high and may be intermittently fluctuating even higher out of spec. That can cause random disconnects, spontaneous re-booting of the modem, and speed and latency problems.
In a self troubleshooting effort to try to obtain better connectivity / more wiggle room, check to see if there are there any excess/unneeded coax cable splitters in the line leading to the modem that can be eliminated/re-configured. Any splitters that remain should be high quality and cable rated for 5-1002 MHz, bi-directional, and no gold colored garbage types like GE, RadioShack, RCA, Philips, Leviton, Magnavox, and Rocketfish from big box stores like Home Depot, Lowes, Target, Wal-Mart etc. Splitters should be swapped with known to be good / new ones to test
If there aren't any unneeded splitters that can be eliminated and if your coax wiring setup can't be reconfigured so that there is a single two way splitter connected directly off of the drop from the street/pole with one port feeding the modem and the other port feeding the rest of the house/equipment with additional splits as needed, and you've checked all the wiring and fittings for integrity and tightness and refresh them by taking them apart then check for and clean off any corrosion / oxidation on the center wire and put them back together again, then perhaps it's best to book a tech visit to investigate and correct.
There is only one splitter for phone modem and internet modem. That splitter was installed by Comcast tech about 4 years ago. I have another splitter to try, but the same setup has been working fine for years. I will also check the box outside where the house wires come into the house, but I bet it is the central box for multiple houses like it was one time before. This behavior usually happens in the winter when it gets really cold.
I could try to use phone 722G modem for both and see if it gets better. Question. Can I provision 722G without support and back to CM500? I have 150/5 and I know 722G can't handle that speed.
It's more likely to be a line problem than a modem problem. And if you used the 722 not too long ago, it may still have its provisioning. Give it a try. If it won't connect, you'll need to call.