About bluesrhythm

Just circling back with everyone - it looks like local support got this fixed up even before ComcastAmir and I were able to start working on it together.  Last Friday I was pretty dead in the water from a connection standpoint - a ton of drops, very unreliable connection speeds.  About noon there was a tech working at the pole right outside the house - not a lot of improvement when he was done, but I noticed upstream power levels had climbed a touch and the downstream levels had dropped but also flattened.  However, there were other trucks working nearby in the neighborhood so I figured work was continuing.  Overnight we dropped completely for quite a while - then came back up, and by about 11am Saturday we were clocking in at about 400Mbit/s and, much more important of late, no noticeable connection drops at all.   Since then (it's now Tuesday morning) I've seen just a sprinkle of connection drops, and only on my ping monitors - I haven't actually noticed any outage.  Speed remains consistently high - from what I can tell I'm actually hitting performance limits on the test gear now, so I may be getting even higher speed at the modem itself.   So, tl;dr - problem was definitely outside the house and, it appears, probably beyond our pole as well, and Comcast got me back in action.     Thanks to everyone who contributed on this thread - I learned a bunch, and I'm sure some of the work we did helped improve in-house performance too, so it was time well spent. ... View more

Thanks ComcastAmir, I sent you my details by private message (yesterday?) - any help would be much appreciated!   Still seeing a lot of dropping, and noticing that the modem keeps losing the lock on the OFDM downstream channel.  Sometimes it will re-establish on its own, sometimes a reboot required to reset everything.  I noticed that the power levels on all the downstream channels are noticably higher than they were on a prior post - not sure if that's just because of the splitter reconfiguration I did (replaced 3-way to modem/dvr/tv with 2-way to modem/another 2-way to dvr/tv) or if Comcast adjusted an amplifier somewhere.  The SNR still looks about the same. Downstream Bonded Channels Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables 1 Locked QAM256 37 675000000 Hz 4.5 dBmV 39.8 dB 0 0 2 Locked QAM256 9 507000000 Hz 2.6 dBmV 40.1 dB 0 0 3 Locked QAM256 10 513000000 Hz 2.6 dBmV 40.1 dB 0 0 4 Locked QAM256 11 519000000 Hz 2.7 dBmV 40.2 dB 0 0 5 Locked QAM256 12 525000000 Hz 2.8 dBmV 40.3 dB 0 0 6 Locked QAM256 13 531000000 Hz 2.7 dBmV 40.3 dB 0 0 7 Locked QAM256 14 537000000 Hz 2.5 dBmV 40.2 dB 0 0 8 Locked QAM256 15 543000000 Hz 2.1 dBmV 40.1 dB 0 0 9 Locked QAM256 16 549000000 Hz 2 dBmV 40.1 dB 0 0 10 Locked QAM256 17 555000000 Hz 1.8 dBmV 39.9 dB 14 24 11 Locked QAM256 18 561000000 Hz 1.9 dBmV 39.9 dB 20 13 12 Locked QAM256 19 567000000 Hz 1.9 dBmV 39.8 dB 17 18 13 Locked QAM256 20 573000000 Hz 2.4 dBmV 40.1 dB 39 36 14 Locked QAM256 21 579000000 Hz 2.8 dBmV 40.2 dB 27 46 15 Locked QAM256 22 585000000 Hz 2.9 dBmV 40.2 dB 36 16 16 Locked QAM256 23 591000000 Hz 3 dBmV 40.1 dB 0 0 17 Locked QAM256 24 597000000 Hz 3.1 dBmV 40.1 dB 0 0 18 Locked QAM256 25 603000000 Hz 3.1 dBmV 40 dB 0 0 19 Locked QAM256 26 609000000 Hz 2.8 dBmV 39.8 dB 0 0 20 Locked QAM256 27 615000000 Hz 2.4 dBmV 39.5 dB 0 0 21 Locked QAM256 28 621000000 Hz 2.2 dBmV 39.5 dB 0 0 22 Locked QAM256 29 627000000 Hz 1.8 dBmV 39.3 dB 0 0 23 Locked QAM256 30 633000000 Hz 1.7 dBmV 39.2 dB 0 0 24 Locked QAM256 31 639000000 Hz 1.6 dBmV 39.1 dB 0 0 25 Locked QAM256 32 645000000 Hz 1.7 dBmV 39.1 dB 0 0 26 Locked QAM256 33 651000000 Hz 1.5 dBmV 39 dB 0 0 27 Locked QAM256 34 657000000 Hz 1.8 dBmV 39.2 dB 0 0 28 Locked QAM256 35 663000000 Hz 2.5 dBmV 39.5 dB 0 0 29 Locked QAM256 36 669000000 Hz 3.4 dBmV 39.8 dB 0 0 30 Locked QAM256 38 681000000 Hz 5.2 dBmV 40.4 dB 0 0 31 Locked QAM256 39 687000000 Hz 5.1 dBmV 40.4 dB 0 0 32 Locked QAM256 40 693000000 Hz 3.5 dBmV 39.9 dB 0 0   Upstream Bonded Channels Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power 1 Locked ATDMA 1 5120 Ksym/sec 36500000 Hz 44.5 dBmV 2 Locked ATDMA 2 5120 Ksym/sec 30100000 Hz 45 dBmV 3 Locked ATDMA 3 5120 Ksym/sec 23700000 Hz 45.5 dBmV 4 Locked ATDMA 4 5120 Ksym/sec 17300000 Hz 45 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   Downstream OFDM Channels Channel Lock Status Modulation / Profile ID Channel ID Frequency Power SNR / MER Active Subcarrier Number Range Unerrored Codewords Correctable Codewords Uncorrectable Codewords 1 Locked 0 159 702000000 Hz 0.6 dBmV 40.5 dB 1546 ~ 2549 3940771 945 0 2 Not Locked 0 0 0 Hz 0 dBmV 0.0 dB 0 ~ 4095 0 0 0   ... View more

EG, thanks lots for the help you've already given me for helping route this, I really appreciate it. ... View more

Although it seems a bit better, still getting quite a few intermittent drops, and as before it seems to be morning that triggers it - we ran completely error/drop free last night from 9pm until about 2am, then at some point between 2am and 8am collected a bunch of failed pings, thousands of correctable and hundreds of uncorrectable codewords, and lost the lock on OFDM channel 1 so we were down to 30Mbps.  Rebooted the CM1150V and came back up at close to 300Mbps (nowhere near the 1Gbps plan we're on), with still a number of drops from then until now (about noon).   Somewhat random item, but I'm clutching at straws here:  last tech here replaced the ground/surge block in the demarc box, and grounded to our house electrical ground (which is right there).  All cable & compute gear is grounded to that same point, so there shouldn't be any ground loops.  BUT ... I recently mounted an antenna on our chimney at the other end of the house for a cell booster, and pounded in a brand new ground over there.  The booster lives in the same closet that the Comcast cable line comes into.  I disconnected the antenna-in coax from the booster, and measured voltage from it's shield to the Comcast line-in shield (i.e. basically measuring voltage from old house ground to a brand new ground on the other side of the house), and I'm reading about 500mV AC.  Not sure if that's normal (line-of-sight distance between the two stakes is about 50', with the house basement in between), or a sign of a dodgy ground on one side or the other.  Would it be worth putting in a new ground for the house to see if it mitigates the drops, or is it all moot since all of the cable gear and the line already share a common ground?  (Thinking probably moot since house ground is also bonded to neutral and up to the utility transformer - a new stake & wire at the house isn't going to budge it if it's wired right).   Problems did NOT start when I put in the cell booster, they predate it - it just gave me a handy measurement opportunity to flail around with.   😀 ... View more

Thanks EG, that makes sense.   Redid my splitters and as expected the upstream power level dropped 2-3dBmV on each channel.  Will see how it does from here! Upstream Bonded Channels Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power 1 Locked ATDMA 1 5120 Ksym/sec 36500000 Hz 43.3 dBmV 2 Locked ATDMA 2 5120 Ksym/sec 30100000 Hz 44.8 dBmV 3 Locked ATDMA 3 5120 Ksym/sec 23700000 Hz 45.8 dBmV 4 Locked ATDMA 4 5120 Ksym/sec 17300000 Hz 45.3 dBmV ... View more

Also, I have a better event log now than the XB6 provided (yay!) - here's the content since power-up.  The momentary internet drops don't seem to be generating an error or warning here in the log, as I'm watching pings fail to multiple addresses (including the gateway address for my IP) nothing is getting added here.   Time Priority Description Mon Aug 17 12:26:22 2020 Critical (3) SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=[redacted];CMTS-MAC=[redacted];CM-QOS=1.1;CM-VER=3.1; Mon Aug 17 12:14:15 2020 Warning (5) Dynamic Range Window violation Mon Aug 17 12:14:15 2020 Warning (5) RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=[redacted];CMTS-MAC=[redacted];CM-QOS=1.1;CM-VER=3.1; Mon Aug 17 12:14:15 2020 Warning (5) Dynamic Range Window violation Mon Aug 17 12:14:15 2020 Warning (5) RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=[redacted];CMTS-MAC=[redacted];CM-QOS=1.1;CM-VER=3.1; Mon Aug 17 12:14:05 2020 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) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=[redacted];CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1; ... View more

Update on status - I got Comcast to commit to send out a line technician to check the node and the pole.  I don't know if they actually did that or not, but I do know that a Comcast tech visited the house (totally unseen, like The Shadow!) because when I went out yesterday to put a better compression fitting on the cable line into the house (wasn't confident in my prior replacement), the ground block/surge protector in the box had been replaced and the old one was left loose in the box.  However, connectivity was still dodgy at best, and downright miserable at times although it appears work may have been being performed nearby.    This morning, back to low speed and/or intermittent connectivity - so I took the plunge and bought a Netgear CM1150V to replace the Technicolor XB6 Comcast had supplied, since the modem is the only thing on-prem that hasn't been replaced, and our issues began at roughly the same time we upgraded to it.  Activated fine, but still getting the intermittent connectivity errors.  Here are the new signal tables from the CM1150V:   Startup Procedure Procedure Status Comment Acquire Downstream Channel 579000000 Hz Locked Connectivity State OK Operational Boot State OK Operational Security Enabled BPI+ IP Provisioning Mode Honor MDD honorMdd(4)   Downstream Bonded Channels Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables 1 Locked QAM256 21 579000000 Hz 0.1 dBmV 40.2 dB 0 0 2 Locked QAM256 1 453000000 Hz 0 dBmV 40 dB 0 0 3 Locked QAM256 2 459000000 Hz -0.4 dBmV 39.8 dB 0 0 4 Locked QAM256 3 465000000 Hz -0.6 dBmV 39.8 dB 0 0 5 Locked QAM256 4 471000000 Hz -0.9 dBmV 39.6 dB 0 0 6 Locked QAM256 5 477000000 Hz -0.8 dBmV 39.7 dB 0 0 7 Locked QAM256 6 483000000 Hz -0.9 dBmV 39.6 dB 0 0 8 Locked QAM256 7 489000000 Hz -1 dBmV 39.5 dB 0 0 9 Locked QAM256 8 495000000 Hz -0.5 dBmV 39.8 dB 0 0 10 Locked QAM256 9 507000000 Hz -0.1 dBmV 40 dB 0 0 11 Locked QAM256 10 513000000 Hz -0.2 dBmV 40 dB 2 0 12 Locked QAM256 11 519000000 Hz -0.3 dBmV 40 dB 1 0 13 Locked QAM256 12 525000000 Hz -0.6 dBmV 40 dB 3 0 14 Locked QAM256 13 531000000 Hz -1.1 dBmV 39.8 dB 3 0 15 Locked QAM256 14 537000000 Hz -1.5 dBmV 39.5 dB 2 0 16 Locked QAM256 15 543000000 Hz -1.9 dBmV 39.4 dB 2 0 17 Locked QAM256 16 549000000 Hz -1.7 dBmV 39.5 dB 2 0 18 Locked QAM256 17 555000000 Hz -1.8 dBmV 39.4 dB 1 0 19 Locked QAM256 18 561000000 Hz -1.5 dBmV 39.5 dB 1 0 20 Locked QAM256 19 567000000 Hz -1.3 dBmV 39.6 dB 0 0 21 Locked QAM256 20 573000000 Hz -0.7 dBmV 39.9 dB 0 0 22 Locked QAM256 22 585000000 Hz 0.3 dBmV 40.2 dB 0 0 23 Locked QAM256 23 591000000 Hz 0.1 dBmV 40 dB 0 0 24 Locked QAM256 24 597000000 Hz -0.1 dBmV 39.8 dB 0 0 25 Locked QAM256 25 603000000 Hz -0.4 dBmV 39.7 dB 0 0 26 Locked QAM256 26 609000000 Hz -0.7 dBmV 39.5 dB 0 0 27 Locked QAM256 27 615000000 Hz -0.9 dBmV 39.2 dB 0 0 28 Locked QAM256 28 621000000 Hz -0.9 dBmV 39.3 dB 0 0 29 Locked QAM256 29 627000000 Hz -1.1 dBmV 39.2 dB 0 0 30 Locked QAM256 30 633000000 Hz -1.2 dBmV 39.1 dB 0 0 31 Locked QAM256 31 639000000 Hz -1.3 dBmV 39 dB 0 0 32 Locked QAM256 32 645000000 Hz -1.1 dBmV 39.1 dB 0 0   Upstream Bonded Channels Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power 1 Locked ATDMA 1 5120 Ksym/sec 36500000 Hz 46.3 dBmV 2 Locked ATDMA 2 5120 Ksym/sec 30100000 Hz 46.8 dBmV 3 Locked ATDMA 3 5120 Ksym/sec 23700000 Hz 47.8 dBmV 4 Locked ATDMA 4 5120 Ksym/sec 17300000 Hz 46.8 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   Downstream OFDM Channels Channel Lock Status Modulation / Profile ID Channel ID Frequency Power SNR / MER Active Subcarrier Number Range Unerrored Codewords Correctable Codewords Uncorrectable Codewords 1 Locked 0 159 702000000 Hz -2.1 dBmV 40.4 dB 1546 ~ 2549 58081722 3611 13 2 Not Locked 0 0 0 Hz 0 dBmV 0.0 dB 0 ~ 4095 0 0 0   Upstream OFDMA Channels Channel Lock Status Modulation / Profile ID Channel ID Frequency Power 1 Not Locked 0 0 0 Hz 0 dBmV 2 Not Locked 0 0 0 Hz 0 dBmV   Current System Time:Mon Aug 17 13:17:46 2020 System Up Time:01:04:36   A few things of note:  I know upstream is bit toward the high side, I'm currently back to Comcast's supplied 3-way splitter that feeds the modem, DVR, and an additional TV box.  New splitters arriving today so I can split line-in to 1) modem and 2) next splitter, with the DVR+TV box on that second splitter (should drop that signal about 3dBmV).  And - the system time is wrong, it's off by an hour, apparently whatever's transmitting it on the upstream side isn't aware of daylight savings time (there's no config option on my side to fix that). ... View more

Turns out my optimism was misplaced - I hadn't checked speed after I removed the splitter and replaced the cable ends, turns out we were error-free but at 30Mbps.  Once I rebooted we came backup up at 300Mbps+ but started getting drops again.  That's been a typical pattern - on any given reboot we'll occasionally hit low speed but fairly solid connection, or back closer to plan speeds but unstable.   Line techs are due out tomorrow to check the node at the street - it's the next link in the chain and hasn't been looked at yet as far as I know.  Given the connection sensitivity to weather/temperature I'm hopeful that'll nail it down - will keep the thread posted! ... View more

Stability was a little better but still pretty spotty yesterday even after removing the splitter (which dropped the upstream power by about 6dBmV as posted above), and was positively terrible this morning even after a couple reboots.  BUT - I had noticed yesterday when temporarily removing the splitter that the connector on the coax line in had a plastic shield on it that made it rather difficult to connect the line to the coupler.  I replaced that (didn't make a difference either way).  Late this morning I paid a visit to the outside drop box and the line into the house had the same type of connector, so I replaced that as well and reconnected the line to the ground block.  It's pretty soon to make a call, but it's been nearly an hour since replacing that connector and I haven't had a single drop yet - I'll keep an eye on it and update this thread shortly. ... View more

Quick update - I just removed the 3-way and replaced with a straight coupler so only the gateway is on the line.  Upstream power levels dropped by about 6dBmV from my prior post.  I'll report back on stability in a couple days, or when my family starts getting really irritated that the TVs are offline, whichever occurs first.   😉   IndexLock StatusFrequencySymbol RatePower LevelModulationChannel Type 1 2 3 4 Locked Locked Locked Locked 36 MHz 30 MHz 23 MHz 17 MHz 5120 5120 5120 5120 42.3 dBmV 42.8 dBmV 43.3 dBmV 42.8 dBmV QAM QAM QAM QAM ATDMA ATDMA ATDMA ATDMA ... View more

Thanks EG, that's very helpful.  There's a coax coupler outside the house in the junction box connecting the line from the street to the line in the house (not a splitter, but I'll inspect the connections for corrosion), and just one splitter in the house but that is a three-way (Comcast-installed) feeding the modem, DVR, and a TV extension all off the line in.  I'll pull that three-way for now (sorry kids, no TV today!) and see if things stabilize.  Either way I'll report back.   What sort of upstream power levels should I be seeing typically?  I can take a look right when I'm having issues and see if they look out of line. ... View more

Lost a few days of connectivity due to tropical storm Isaias - but we're back up, and although it seems a little more stable the pattern still seems to hold that at least once per day we'll start seeing drops and degradation of the connection, and a reboot of the modem gets us reset and working fine for many hours after that.   I've been considering purchasing my own modem (likely a Netgear CM1150V since we use the voice service) - figure that might solve the probelm if the modem itself is degrading the connection over time.  But I'm pretty reluctant to make the switch as it seems that would just add another layer of complication to solving the issue if it's not the modem (i.e. I don't want to get into a spiral of "Your third-party modem must be the problem, things look fine") - I'd rather get this resolved while all the problems are on Comcast gear + wire, then think about a modem shift. ... View more

Here's the latest set - hopefully timely, I've just started seeing connectivity glitches after my last reboot about 6 hours ago.  I also checked the logs for messages but they only show my admin login and the startup of the radio & device data harvesting.   Downstream: Index 33 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 34 35 36 37 38 39 40 159   Lock Status Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Locked Frequency 651 MHz 507 MHz 513 MHz 519 MHz 525 MHz 531 MHz 537 MHz 543 MHz 549 MHz 555 MHz 561 MHz 567 MHz 573 MHz 579 MHz 585 MHz 591 MHz 597 MHz 603 MHz 609 MHz 615 MHz 621 MHz 627 MHz 633 MHz 639 MHz 645 MHz 657 MHz 663 MHz 669 MHz 675 MHz 681 MHz 687 MHz 693 MHz 702 MHz 620600000 SNR 38.3 dB 39.2 dB 39.4 dB 39.7 dB 39.8 dB 39.8 dB 39.8 dB 39.6 dB 39.5 dB 39.4 dB 39.1 dB 39.2 dB 39.3 dB 39.7 dB 39.8 dB 39.7 dB 39.6 dB 39.5 dB 39.3 dB 39.1 dB 39.3 dB 39.0 dB 38.7 dB 38.4 dB 38.6 dB 38.4 dB 38.6 dB 39.0 dB 38.9 dB 39.9 dB 39.9 dB 39.7 dB 39.5 dB NA Power Level -4.5 dBmV -4.5 dBmV -4.2 dBmV -3.8 dBmV -3.2 dBmV -3.1 dBmV -3.2 dBmV -3.6 dBmV -3.9 dBmV -4.4 dBmV -4.6 dBmV -4.8 dBmV -4.3 dBmV -3.3 dBmV -2.9 dBmV -2.9 dBmV -2.9 dBmV -3.1 dBmV -3.2 dBmV -3.1 dBmV -2.8 dBmV -3.4 dBmV -4.2 dBmV -4.6 dBmV -4.4 dBmV -4.4 dBmV -3.9 dBmV -3.0 dBmV -2.0 dBmV 0.8 dBmV 0.0 dBmV 0.8 dBmV -4.3 dBmV NA Modulation 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM 256 QAM OFDM OFDM   Upstream: IndexLock StatusFrequencySymbol RatePower LevelModulationChannel Type 1 2 3 4 Locked Locked Locked Locked 36 MHz 30 MHz 23 MHz 17 MHz 5120 5120 5120 5120 48.3 dBmV 48.3 dBmV 48.8 dBmV 48.3 dBmV QAM QAM QAM QAM ATDMA ATDMA ATDMA ATDMA   CM Error Codewords: Index 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 Unerrored Codewords 392971927 949458298 949463365 949467626 949473986 949477908 949483935 949488746 949497708 949502021 949507527 949511738 949517762 949522755 949528778 949533711 949545458 949550306 949555209 949560705 949565170 949570441 949575725 949581194 949585865 949591372 949597226 949600949 949605820 949609849 949612169 949614448 392971927 Correctable Codewords 2762 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2762 Uncorrectable Codewords 113 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 113 ... View more