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Cm600 connection issues xfinity
I've been having connection issues with modem on and off for about 6 months. It usually happens when my router, or modem loses power and starts back up. My router is a asus RT-AX86U Pro running asuswr...
- So xfinity tech came out today and traced my coaxial cable back to a splitter. My apartment complex is old and the splitter was hidden. To make it worse, the previous tenants set it up with the input/output cables reversed. That combined with my older modem is what was causing the issues. The tech removed the splitter and my old router is now able to connect to 4 Upstream channels.
I'm also getting a new modem this weekend and went with a surfboard sb8200.
Thanks everyone for the help and input. It's much appreciated. Happy Holidays
| Frequency start Value | |
| This field below allows you to modify the frequency the cable modem start with its scan during initialization and registration. Enter the new start frequency and restart the cable modem for it to take effect. | |
|
Startup Procedure
| Procedure | Status | Comment |
| Acquire Downstream Channel | 459000000 Hz | Locked |
| Connectivity State | OK | Operational |
| Boot State | OK | Operational |
| Security | Enable | BPI+ |
| IP Provisioning Mode | Honor MDD | IPv6 only |
<tabindex=-1>Downstream Bonded Channels</tabindex=-1>
| Channel | Lock Status | Modulation | Channel ID | Frequency | Power | SNR | Correctables | Uncorrectables |
| 1 | Locked | QAM256 | 5 | 459000000 Hz | -0.1 dBmV | 42.5 dB | 0 | 0 |
| 2 | Locked | QAM256 | 22 | 561000000 Hz | 0.3 dBmV | 41.9 dB | 0 | 0 |
| 3 | Locked | QAM256 | 23 | 567000000 Hz | 0.4 dBmV | 42.1 dB | 0 | 0 |
| 4 | Locked | QAM256 | 24 | 573000000 Hz | 0.6 dBmV | 42.2 dB | 1 | 0 |
| 5 | Locked | QAM256 | 1 | 435000000 Hz | 0.4 dBmV | 42.4 dB | 0 | 0 |
| 6 | Locked | QAM256 | 2 | 441000000 Hz | -0.1 dBmV | 42.0 dB | 0 | 0 |
| 7 | Locked | QAM256 | 3 | 447000000 Hz | -0.7 dBmV | 41.8 dB | 0 | 0 |
| 8 | Locked | QAM256 | 4 | 453000000 Hz | 0.6 dBmV | 42.9 dB | 0 | 0 |
| 9 | Locked | QAM256 | 6 | 465000000 Hz | 0.4 dBmV | 42.8 dB | 0 | 0 |
| 10 | Locked | QAM256 | 7 | 471000000 Hz | 0.6 dBmV | 42.8 dB | 0 | 0 |
| 11 | Locked | QAM256 | 8 | 477000000 Hz | -0.4 dBmV | 42.0 dB | 0 | 0 |
| 12 | Locked | QAM256 | 9 | 483000000 Hz | 0.6 dBmV | 42.6 dB | 0 | 0 |
| 13 | Locked | QAM256 | 10 | 489000000 Hz | 0.1 dBmV | 42.3 dB | 0 | 0 |
| 14 | Locked | QAM256 | 11 | 495000000 Hz | -0.1 dBmV | 42.4 dB | 0 | 0 |
| 15 | Locked | QAM256 | 12 | 501000000 Hz | 0.7 dBmV | 43.0 dB | 0 | 0 |
| 16 | Locked | QAM256 | 13 | 507000000 Hz | 0.3 dBmV | 38.6 dB | 0 | 0 |
| 17 | Locked | QAM256 | 14 | 513000000 Hz | -0.4 dBmV | 42.4 dB | 0 | 0 |
| 18 | Locked | QAM256 | 15 | 519000000 Hz | -0.5 dBmV | 42.0 dB | 0 | 0 |
| 19 | Locked | QAM256 | 16 | 525000000 Hz | -1.0 dBmV | 41.9 dB | 0 | 0 |
| 20 | Locked | QAM256 | 17 | 531000000 Hz | -0.4 dBmV | 41.9 dB | 0 | 0 |
| 21 | Locked | QAM256 | 18 | 537000000 Hz | -0.6 dBmV | 41.9 dB | 0 | 0 |
| 22 | Locked | QAM256 | 19 | 543000000 Hz | -0.5 dBmV | 41.8 dB | 0 | 0 |
| 23 | Locked | QAM256 | 20 | 549000000 Hz | -0.1 dBmV | 41.9 dB | 0 | 0 |
| 24 | Locked | QAM256 | 21 | 555000000 Hz | -0.3 dBmV | 41.9 dB | 1 | 0 |
<tabindex=-1>Upstream Bonded Channels</tabindex=-1>
| Channel | Lock Status | US Channel Type | Channel ID | Symbol Rate | Frequency | Power |
| 1 | Locked | ATDMA | 3 | 5120 Ksym/sec | 22800000 Hz | 57.0 dBmV |
| 2 | Not Locked | Unknown | 0 | 0 Ksym/sec | 0 Hz | 0.0 dBmV |
| 3 | Not Locked | Unknown | 0 | 0 Ksym/sec | 0 Hz | 0.0 dBmV |
| 4 | Not Locked | Unknown | 0 | 0 Ksym/sec | 0 Hz | 0.0 dBmV |
| 5 | Not Locked | Unknown | 0 | 0 Ksym/sec | 0 Hz | 0.0 dBmV |
| 6 | Not Locked | Unknown | 0 | 0 Ksym/sec | 0 Hz | 0.0 dBmV |
| 7 | Not Locked | Unknown | 0 | 0 Ksym/sec | 0 Hz | 0.0 dBmV |
| 8 | Not Locked | Unknown | 0 | 0 Ksym/sec | 0 Hz | 0.0 dBmV |
Cable Connections data is good.
Have the ISP check the signal and line quality UP to the modem. Be sure the ISP provisions the modem correctly.
Be sure there are no coax cable line splitters in the between the modem and ISP service box.
Be sure your using good quality RG6 coax cable up to the modem.
Start with removing any amplifiers, signal attenuators, or splitters from the coax.
From there check the line for kinks, damage, moisture in the line.
Check the connectors for improperly made ends, foil touching the copper coax line, loose connections, bad/old/cheap connectors, or corroded connections. Replace them if you do.
Be sure to power OFF the modem for 1 minute then back ON.
https://community.netgear.com/t5/Cable-Modems-Routers/General-info-and-Troubleshooting-for-Cable-Modems/m-p/1530376#M12853
https://kb.netgear.com/24311/Power-level-guidelines-for-a-NETGEAR-cable-modem-router
https://www.duckware.com/tech/solving-intermittent-cable-modem-issues.html
https://highspeed.tips/docsis-events/
The CM600 is of older model so you may need to upgrade the modem at some point.
Your cable connection is not good. At an upstream of 57dbmv, we'd expect your downstream to be pretty low. Probably in the -7.5 to -15dbmv. That high of an upstream indicates the modem has to send significant power just to reach the hub/cmts. And it tends to be reciprocal. So, if it's takes that much power for the modem to send data to the hub/cmts, it should have lower downstream values. Yours doesn't. It's sitting about 0 (ish). Something in the line is causing resistance one way (like specific attenuators or cable connection issues), or you're using an amplifier to boost a sketchy signal.
Back to checking the line for amplifiers or other issues because that isn't a good signal level. They need to be roughly representative of each other's values.
and Kitsap is correct. You're coming up on end of life for the cm600. Xfinity is pushing docsis 3.1 devices for speed tiers.
Keep on eye on their mid-split list for the modems with the higher upstream. You don't think you need it until you have it and appreciate the faster uploads.
