[Connectivity] Could This be Modem or Line Issue?

Author	All Replies
papitosabe join:2012-06-07	[Connectivity] Could This be Modem or Line Issue? Comcast Performance on SB5101 My first post guys. And I'm a complete newb but have been searching all night and the following is what I came up with. I've reset, power down, switched power adapters, removed router..so now coming from wall to modem to pc . Its been getting worse this past week. Drop offs were about 3x's/day...yesterday, pretty much all day... now,it won't connect at all.. the modem now has a solid green on top, and flashing green on 2nd light, 3rd and 4th light nothing.. solid connectivity orange at bottom.. no splitter.. i only have internet...cable is pretty sturdy, from comcast..live in an apartment... Downstream freq 703750000 HZ sig to noise ratio 16.6db, but was 24 - 29 earlier -10.8 dBmv now, but has been 14 rarely, but mostly 24..has been up to 27 after a reset.. Upstream -noting at the moment but had something earlier.. 8.3 dBmV now, but most of the time it has been 51 rarely, mostly 54 wanted to see if was modem before getting a tech . any advice appreciated logs currently 2012-06-07 07:39:42 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response. 2012-06-07 07:39:28 3-Critical R002.0 No Ranging Response received - T3 time-out (US 4) 2012-06-07 07:39:23 3-Critical R007.0 Unicast Ranging Received Abort Response - Re- initializing MAC 2012-06-07 07:38:58 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing 2012-06-07 07:38:55 6-Notice M572.0 T1 No Ucd Timeout - Reinitialize MAC... 2012-06-07 07:38:55 3-Critical U001.0 No UCD's Received - Timeout 2012-06-07 07:38:45 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing 2012-06-07 07:38:32 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing 2012-06-07 07:38:32 6-Notice M572.0 Ds Lock Failed - Reinitialize MAC... 2012-06-07 07:38:31 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing 2012-06-07 07:38:31 6-Notice M572.0 Rng Rsp Abort Status - Reinitialize MAC... 2012-06-07 07:38:31 3-Critical C206.0 DCC aborted unable to communicate on new upstream channel 2012-06-07 07:38:31 3-Critical R007.0 Unicast Ranging Received Abort Response - Re- initializing MAC 1970-01-01 00:00:15 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response. 1970-01-01 00:02:06 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing 1970-01-01 00:02:02 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing 1970-01-01 00:02:00 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing 1970-01-01 00:01:56 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing 1970-01-01 00:01:24 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing 1970-01-01 00:01:23 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing 1970-01-01 00:01:22 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing 1970-01-01 00:01:21 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing 1970-01-01 00:01:18 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing 1970-01-01 00:01:18 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing 1970-01-01 00:01:06 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing 1970-01-01 00:01:05 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing 1970-01-01 00:01:00 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing 1970-01-01 00:00:59 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing 1970-01-01 00:00:16 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing 1970-01-01 00:00:16 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing 1970-01-01 00:00:06 6-Notice M571.1 Ethernet link up - ready to pass packets 1970-01-01 00:00:02 6-Notice M571.4 Ethernet link dormant - not currently active 1970-01-01 00:00:06 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing 2012-06-07 07:33:21 6-Notice M573.0 Modem Is Shutting Down and Rebooting... 2012-06-07 07:33:21 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing 2012-06-07 07:33:09 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing 2012-06-07 07:33:09 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing 2012-06-07 07:32:57 3-Critical R007.0 Unicast Ranging Received Abort Response - Re- initializing MAC 2012-06-07 07:32:31 6-Notice M572.0 Rng Rsp Abort Status - Reinitialize MAC... 2012-06-07 07:32:31 3-Critical C206.0 DCC aborted unable to communicate on new upstream channel 2012-06-07 07:32:31 3-Critical R007.0 Unicast Ranging Received Abort Response - Re- initializing MAC 1970-01-01 00:00:15 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response. 1970-01-01 00:00:04 6-Notice M571.1 Ethernet link up - ready to pass packets 1970-01-01 00:00:02 6-Notice M571.4 Ethernet link dormant - not currently active 2012-06-07 07:29:04 6-Notice M573.0 Modem Is Shutting Down and Rebooting... 2012-06-07 07:29:02 6-Notice M572.0 T1 No Ucd Timeout - Reinitialize MAC... 2012-06-07 07:29:02 3-Critical U001.0 No UCD's Received - Timeout 2012-06-07 07:28:51 6-Notice M572.0 T1 No Ucd Timeout - Reinitialize MAC... 2012-06-07 07:28:51 3-Critical U001.0 No UCD's Received - Timeout 2012-06-07 07:28:41 6-Notice M572.0 T1 No Ucd Timeout - Reinitialize MAC... 2012-06-07 07:28:41 3-Critical U001.0 No UCD's Received - Timeout 2012-06-07 07:28:30 6-Notice M572.0 T1 No Ucd Timeout - Reinitialize MAC... 2012-06-07 07:28:30 3-Critical U001.0 No UCD's Received - Timeout 2012-06-07 07:28:19 6-Notice M572.0 T1 No Ucd Timeout - Reinitialize MAC... 2012-06-07 07:28:19 3-Critical U001.0 No UCD's Received - Timeout 2012-06-07 07:28:09 6-Notice M572.0 T1 No Ucd Timeout - Reinitialize MAC... 2012-06-07 07:28:09 3-Critical U001.0 No UCD's Received - Timeout 2012-06-07 07:27:58 6-Notice M572.0 T1 No Ucd Timeout - Reinitialize MAC... 2012-06-07 07:27:58 3-Critical U001.0 No UCD's Received - Timeout 2012-06-07 07:27:47 6-Notice M572.0 T1 No Ucd Timeout - Reinitialize MAC... 2012-06-07 07:27:47 3-Critical U001.0 No UCD's Received - Timeout 2012-06-07 07:27:37 6-Notice M572.0 T1 No Ucd Timeout - Reinitialize MAC... 2012-06-07 07:27:37 3-Critical U001.0 No UCD's Received - Timeout 2012-06-07 07:27:26 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing 2012-06-07 07:26:58 3-Critical R007.0 Unicast Ranging Received Abort Response - Re- initializing MAC 2012-06-07 07:26:30 6-Notice M572.0 Rng Rsp Abort Status - Reinitialize MAC... 2012-06-07 07:26:30 3-Critical C206.0 DCC aborted unable to communicate on new upstream channel 2012-06-07 07:26:30 3-Critical R007.0 Unicast Ranging Received Abort Response - Re- initializing MAC 1970-01-01 00:00:32 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response. 1970-01-01 00:00:19 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing 1970-01-01 00:00:06 6-Notice M571.1 Ethernet link up - ready to pass packets 1970-01-01 00:00:06 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing 1970-01-01 00:00:02 6-Notice M571.4 Ethernet link dormant - not currently active 2012-06-07 07:23:41 6-Notice M573.0 Modem Is Shutting Down and Rebooting... 2012-06-07 07:23:30 6-Notice M572.0 Rng Rsp Abort Status - Reinitialize MAC... 2012-06-07 07:23:30 3-Critical C206.0 DCC aborted unable to communicate on new upstream channel 2012-06-07 07:23:30 3-Critical R007.0 Unicast Ranging Received Abort Response - Re- initializing MAC 2012-06-07 07:22:14 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response. 2012-06-07 07:22:03 3-Critical R007.0 Unicast Ranging Received Abort Response - Re- initializing MAC 2012-06-07 07:21:35 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing 2012-06-07 07:21:32 6-Notice M572.0 T1 No Ucd Timeout - Reinitialize MAC... 2012-06-07 07:21:32 3-Critical U001.0 No UCD's Received - Timeout 2012-06-07 07:21:21 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing 2012-06-07 07:21:08 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing 2012-06-07 07:21:08 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing 2012-06-07 07:21:00 3-Critical R007.0 Unicast Ranging Received Abort Response - Re- initializing MAC 2012-06-07 07:20:30 6-Notice M572.0 Rng Rsp Abort Status - Reinitialize MAC... 2012-06-07 07:20:30 3-Critical C206.0 DCC aborted unable to communicate on new upstream channel 2012-06-07 07:20:30 3-Critical R007.0 Unicast Ranging Received Abort Response - Re- initializing MAC 2012-06-07 07:19:38 6-Notice M571.1 Ethernet link up - ready to pass packets 2012-06-07 07:19:36 6-Notice M571.4 Ethernet link dormant - not currently active 2012-06-07 07:19:22 6-Notice M571.1 Ethernet link up - ready to pass packets 1970-01-01 00:00:16 3-Critical D003.0 DHCP WARNING - Non-critical field invalid in response. 1970-01-01 00:00:02 6-Notice M571.4 Ethernet link dormant - not currently active 2012-06-07 07:07:00 6-Notice M572.0 Ds Lock Failed - Reinitialize MAC... 2012-06-07 07:06:59 6-Notice M572.0 T1 No Ucd Timeout - Reinitialize MAC... 2012-06-07 07:06:59 3-Critical U001.0 No UCD's Received - Timeout 2012-06-07 07:06:48 6-Notice M572.0 T1 No Ucd Timeout - Reinitialize MAC... 2012-06-07 07:06:48 3-Critical U001.0 No UCD's Received - Timeout 2012-06-07 07:06:38 6-Notice M572.0 T1 No Ucd Timeout - Reinitialize MAC..
	to forum · permalink · 2012-06-07 10:50:41 ·
gar187er I do this for a living join:2006-06-24 Dover, DE kudos:4	most likely a cable issue, not the modem....bad line to the apartment, or splitter...who knows....but the flashing 2nd light shows that its not locking on the downstream channels.....without those, the modem cant go anywhere....call in for a tech visit...downstream issues are fairly easy to resolve for techs... -- I'm better than you!
	to forum · permalink · 2012-06-07 11:05:19 ·
graysonf Premium,MVM join:1999-07-16 Fort Lauderdale, FL	reply to papitosabe said by papitosabe: Upstream -noting at the moment but had something earlier.. 8.3 dBmV now, but most of the time it has been 51 rarely, mostly 54 This has been my recent experience on a poor coax run of 20+ year old RG59 with three splitters on the line. The connection was like a yo-yo, dropping many times a day and staying down for periods up to four hours. Rebooting the modem would usually get it to reconnect but it would not stay up long. Upstream 8.3dBmv - Not a real number, but will be seen when the modem is unable to connect. Upstream 51dBmv - Satisfactory, but getting close to becoming a problem. Upstream channels will bond. Upstream 54dBmv - Marginal, probably close to upper limit. Upstream channels might not bond. Upstream 57dBmv - Connection unstable drops likely if it will connect at all, no upstream channel bonding. Here is a smokeping plot showing only some of the drops, the resolution of the graph over this period of time can't show the shorter outages. »/r3/smokeping.···f0bf.CA1 I did an online chat with support when the connection was up. They did a line test and said the connection was "horrible." They scheduled a tech to come out. Comcast was out to my place this past Tuesday and ran a completely new RG6 line from the pedestal to the room where the modem and a TV are. This required one splitter. Upstream now runs between 46.5-47.0 dBmv and the connection is rock solid. Suggest you contact support and get a line test. Good luck.
	to forum · permalink · 2012-06-07 11:10:27 ·

EG The wings of love Premium join:2006-11-18 Union, NJ kudos:9	said by graysonf: Upstream 51dBmv - Satisfactory, but getting close to becoming a problem. Upstream channels will bond. Upstream 54dBmv - Marginal, probably close to upper limit. Upstream channels might not bond. Upstream 57dBmv - Connection unstable drops likely if it will connect at all, no upstream channel bonding. FWIW, and in my experience and opinion, in real world conditions, these figures are not written in stone. Each end users environments and equipment / hardware can be very different. So can the accuracy of any given modem's measuring mechanism. I've seen disconnections at 53 dB.
	to forum · permalink · 2012-06-07 11:44:46 ·
papitosabe join:2012-06-07	reply to papitosabe so i called comcast..she tried to send a link to modem or whatever its called..and she didn't get a hit..so said its either modem or line issue, if modem, i'll be charged for tech..tech to be out sat 8am-8pm (lol)..also, just rebooted modem..not connected to anything so not sure if this means anything... the 1st light still solid green, then the send and receive both started flashing green, and the onlight light was solid green..then a few seconds later the last 2 (pc and standby)flashed solid orange, and then went into a reboot phase... the only thing i'm worried is that its the modem, then i'll have to pay the tech and get a new modem...or I may get a modem, see if that works, if not, i can return the modem...
	to forum · permalink · 2012-06-07 12:35:00 ·
gar187er I do this for a living join:2006-06-24 Dover, DE kudos:4	no such thing as a hit to a modem....dont worry bout the charge...9/10 customers arent charged. -- I'm better than you!
	to forum · permalink · 2012-06-07 12:38:21 ·
papitosabe join:2012-06-07	she didn't say hit..she said something else..i forget..i'm a complete newb...just learning the past 5 hrs from reading... ok, so here is what i did...i went to the closet in my bedroom..i jimmy'd a panel...had one line coming in, with a splitter to 3 cables, 1 being the living room...i disconnected the splitter, to get the main line plugged into the modem...lights came on fine...then connected to wireless router... so signal is going thru 1 wall from living room.. speedtest only shows 10mbps, used to be 23... but i am connecting... .modem shows downstream freq 633000000 34.8 dB -9.2 dBmV Upstream freq 31800000 power 43.7 dBmv how do the above numbers look? logs look fine, says ethernet link up ready to pass packets, but also line below says ethernet link dormant - not currently active again, i'm a complete newb to this stuff, but i just did what I could..so at least i know its not the modem...
	to forum · permalink · 2012-06-07 13:00:55 ·
graysonf Premium,MVM join:1999-07-16 Fort Lauderdale, FL	said by papitosabe: Upstream freq 31800000 power 43.7 dBmv how do the above numbers look? That upstream power looks great. Mine is 46.5 on about 100 feet of brand new RG6 with one splitter on it A splitter adds 3.5dbm, so I would have the same ~43.x as you do without it. Sounds like you may have a bad line beyond the splitter, or the splitter itself is bad, or both.
	to forum · permalink · 2012-06-07 13:12:08 ·
papitosabe join:2012-06-07	reply to papitosabe thanks y'all... lol...so now i'm getting a wireless connection of 14mbps on my tablet...and 3mbps wireless on my pc...but thats a different issue...gotta learn how to configure stuff i guess...there goes another few hours...but thanks again for the responses ...
	to forum · permalink · 2012-06-07 14:04:45 ·
papitosabe join:2012-06-07	Alrighty...so tech comes out...puts his line checker in the living room and the bedroom closet and says there is no signal at all... so the other techs need to come out..so i say, thats weird because an hour ago I connected the modem to the bedroom (not closet) and I was online just fine...he says, well now, there is nothing, if you go online now, you won't connect, i just checked... so he leaves, and I grab him b4 he leaves...i asked him if he'd wait so that i can connect the modem to the closet.. i could tell he was a little nervous, started babbling... so i connect it, then the wireless router...i turned on my xbox..and i got a xbox live connection...he says but still you won't stay on, there is no signal.. i turned it off, and used my tablet..netspeed actually showed 20mbps, which i'd never seen...but he reinterated, no signal, and that I wouldn't stay on... so i asked that what that was called...he didn't answer, i said dbmv? he said yea, that...i said what is it? he said -29...so i checked on my tablet and it showed -9...he said but my machine is more accurate...it should be between 8 and -8...so still we'd still need techs if that was an accurate reading... then he said my living room connection would work once the techs did their thing downstairs...i said that doesn't make sense, why is my modem working off the main line from closet and bedroom, but not the living room...we went back and forth at least 5 times... then he said, oh, then it wouldn't be us..we don't touch the lines inside the apt...your apt will have to do that... but we still need techs to fix the dbmv issue... so i know what is going on here...he could and should have figured it was the line going from the closet to the living room since i got no modem connection from that...but i did get a connection from the bedroom, and from the main line in the closet...its in their, not comcast's, best interest to get their fellow techs sent out so they will all get their hours...i bet a could have a perfectly working line, and gottent the same answer...sorry for the long post...just wanted to convey what happened...
	to forum · permalink · 2012-06-09 18:17:45 ·

US Cable Support > Comcast HSI > [Connectivity] Could This be Modem or Line Issue?