Thanks for the guide on how to use 2.5Gb/s port as a WAN port. I did that switch and it works, but my speed did not change - still about 800Mb/s download. I am OK with that, as for last 10 days I had 0 disconnects and that is much more important for me than the speed. Thanks again for all your help!
After not having an issue since the late fall (had multiple daily 'pauses' in the internet where the modem appeared fine but little to no internet connectivity for a few minutes each time) we just had another from around 9:25am to 9:35am this morning. Hopefully this is an isolated event and not a return to unreliable connectivity interrupting conference calls and connections to my Linux machines over office VPN.
I've been experiencing some intermittent internet connection failures and i started by swapping my Router out and then i looked into my modem and gathered some log / signal information. I notice my upstream signal is a bit high at above 40. Downstream seem good. I then looked through the forum and found out that upstream can be caused by bad outside cable. I looked outside and notice that my cable is exposed to elements along my driveway under a edge of trees. I was wondering if somebody can look at my modem logs and tell me if they confirm it's upstream signal the issue. I also included errors form my modem log. This all started end of March and continues to get errors now.
Downstream Bonding Channel Value
Channel ID 23 21 22 20 32 2 3 4
Frequency 693000000 Hz 681000000 Hz 687000000 Hz 675000000 Hz 843000000 Hz 849000000 Hz 855000000 Hz 861000000 Hz
Signal to Noise Ratio 38 dB 38 dB 38 dB 37 dB 38 dB 38 dB 38 dB 38 dB
Downstream Modulation QAM256 QAM256 QAM256 QAM256 QAM256 QAM256 QAM256 QAM256
The Downstream Power Level reading is a snapshot taken at the time this page was requested. Please Reload/Refresh this Page for a new reading
4 dBmV 4 dBmV 3 dBmV 3 dBmV 2 dBmV 3 dBmV 3 dBmV 3 dBmV
Upstream Bonding Channel Value
Channel ID 5 6 7 8
Frequency 21100000 Hz 25900000 Hz 32300000 Hz 38700000 Hz
Ranging Service ID 4610 4610 4610 4610
Symbol Rate 2.560 Msym/sec 5.120 Msym/sec 5.120 Msym/sec 5.120 Msym/sec
Power Level 38 dBmV 39 dBmV 40 dBmV 40 dBmV
Upstream Modulation  QPSK
Ranging Status Success Success Success Success
Signal Stats (Codewords) Bonding Channel Value
Channel ID 23 21 22 20 32 2 3 4
Total Unerrored Codewords 8130755556 8130742887 8130764624 8130773395 8130738979 8130738403 8130740273 8130740650
Total Correctable Codewords 401 60 60 2 60 17 31 33
Total Uncorrectable Codewords 624 512 588 511 588 717 709 1407
(Removed data - Keep personal info private)
@Longpar3 if you can get back into your previous post, can you delete the log events as that has the modem MAC address which shouldn't be posted in an open forum.
Also, can you try copying the all of the signal level tables and error table, one at a time and paste them into a post. If you have a look at the following post, you can see what they will look like when the tables are pasted into a post:
So, if you place your mouse just ahead of the first character in the table, hold down the shift key, and then arrow down and to the right, to just after the last character in the bottom right hand corner of the OFDM column, the whole table will be selected for copying. Then, with that area selected, right click in that area, select "copy" and then paste that into a new post. As you scroll down and to the right, the whole table view should shift automatically to the right so that the right hand columns are in view as you scroll down and to the right. Note that you can also do this by using the mouse instead of the arrow keys.
Please copy the downstream signal levels, the error codeword table and the upstream signal levels as well.
Looking at the downstream data that is posted, there are only 8 channels worth of data posted. There should be 32 QAM channels and two OFDM channels in the table. Are you only seeing 8 channels in that table? If so, that would probably indicate that you have an external cable and/or connector issue. If you reboot/restart the modem and after the reboot/restart, the user interface displays all 32 QAM channels and 2 OFDM channels (with just 1 channel enabled), to me, that confirms that you have an external cable/connector issue. Over time, that display will go back down to the same initial condition. The reboot/restart will temporarily bring the modem back to a normal operating condition, but, it won't solve the external cable/connector issue. That requires a field tech to inspect the cable and its connectors. So, pull the power from the modem, wait 10 to 15 seconds and plug it back in. Then check the signal levels to see what shows up.
The best time to call tech support for a signal check is when the modem is showing a reduced number of QAM and OFDM channels running. That signal check will automatically fail, and the result should be a discussion to dispatch a field tech to your home. If the tech asks you to restart the modem and then declares victory when the modem fires up all channels as it should, you should indicate that this doesn't solve the problem as you would have already seen this cycle. Hate to say it, but, this is the techs attempt to kick the can down the road for someone else to solve. If you really have a cable signal issue, the solution is to dispatch a field tech, and sometimes, that requires more than one visit. Don't hesitate to call in, multiple times and more than once a day if necessary until the problem is resolved.
I have no idea whats up, but last few days ago I noticed my OFDMA is enabled on my cable modem again. And today, once again I am experiencing intermittent high latency.
My Internet was problem free ever since it was disabled and now the headache returns.
Hey I'm not too sure if anyone can help with this issue. I've already called in twice and the issue seems to be unknown. Maybe someone else has experienced this ? So basically my internet is getting 6-8 lag spikes at exactly every 4 minutes which is very odd. I checked all devices in my home and they all get the same interference. I've done a lot of testing for this and its been happening for about a week now. If someone knows the issue please help me out. Thanks 🙂
Welcome to the community!
Sorry to hear that you're experiencing intermittency! We'll be happy to assist. To help get to the bottom of your experience are you able to complete the troubleshooting steps available here?
If you're able to replicate the packet loss using command prompt and a wired connection to your modem we'll be able to assist in isolating it with you.
If you have any questions at all let us know!