Macroblocking/packet loss on TWC?

[LoadStar]

Ok, my video quality has been just fine up until the last couple of days, using TWC... I've not had any packet loss to speak of, my RoadRunner has been just fine, etc. I haven't changed anything in the last several months regarding my cable, so I don't think it's anything I've done.

However, in the last couple of days, I've noticed every couple of minutes, no matter what channel I watch, I'm getting packet loss, exhibited by a brief blip of audio drop and a garbled image. It only lasts for a split second, then it's fine. Between blips, the  video and audio is perfectly fine.

Is anyone else noticing this all of a sudden?

[Retired]

We moved out here to West Bend the end of August and had Charter cable installed at that time. Have had no problems until the last week then blocking,  sound drops and screen freezing over and over for periods up to around a half hour then all is ok. Most noticeable on analog channels 30 to 99. Could be sunspots, I believe this is supposed to be an active period.

[mhz40]

Ok, my video quality has been just fine up until the last couple of days, using TWC... I've not had any packet loss to speak of, my RoadRunner has been just fine, etc. I haven't changed anything in the last several months regarding my cable, so I don't think it's anything I've done.

However, in the last couple of days, I've noticed every couple of minutes, no matter what channel I watch, I'm getting packet loss, exhibited by a brief blip of audio drop and a garbled image. It only lasts for a split second, then it's fine. Between blips, the  video and audio is perfectly fine.

Is anyone else noticing this all of a sudden?

Problems like this are generally very localized, unless its a source problem - - then everyone experiences problems. If you can, go into diagnostics and check your bit-error rate. I believe its displayed on the tuning page of diagnostics (can't remember now, as I have been running the new navigator just coming out).Anything with a -8 or -9 scientific notation is fine (ie: 6.7 x 10-8). -7's are on the edge of the decoders' error correction capabilities, which could be your problem.
If you have an in-house amp from anyone besides the cable company, take it out and see if things improve.  Otherwise, it may be best if you call in for a service call.  It is likely that there is nothing you can do to resolve this on your own.

[LoadStar]

Problems like this are generally very localized, unless its a source problem - - then everyone experiences problems. If you can, go into diagnostics and check your bit-error rate. I believe its displayed on the tuning page of diagnostics (can't remember now, as I have been running the new navigator just coming out).Anything with a -8 or -9 scientific notation is fine (ie: 6.7 x 10-8). -7's are on the edge of the decoders' error correction capabilities, which could be your problem.
If you have an in-house amp from anyone besides the cable company, take it out and see if things improve.  Otherwise, it may be best if you call in for a service call.  It is likely that there is nothing you can do to resolve this on your own.

Thanks for the help. My signal level normally hovers in the 10 -9 range... all of a sudden tonight it took a nosedive to 10 -6 range.

I don't currently have a signal amp on the line, but I do have a bi-d amp... would it be helpful or harm to try adding that into the loop? And what would cause the signal level to nosedive like that?

[mhz40]

Thanks for the help. My signal level normally hovers in the 10 -9 range... all of a sudden tonight it took a nosedive to 10 -6 range.

I don't currently have a signal amp on the line, but I do have a bi-d amp... would it be helpful or harm to try adding that into the loop? And what would cause the signal level to nosedive like that?

It's not the level, it's the quality of the signal.  256 QAM works well, but everything has to be right... all the way to the tuner.  It's anyones guess what changed - - - that is why test equipment was invented!

[LoadStar]

Ok, continuing on this thread... no, I haven't called for a service call, mostly because...

The problem, as I've noticed, seems to only rear it's ugly head at night. During the day, picture quality is great, BER rates are in the 10-9 range... no problems. Come evening, BER rates drop to the 10-4 to 10-6 range. And unfortunately, the problems really get bad well after the service appointments would end for the night.

I've torn my system apart, swapped out cables, swapped cable boxes, even got a splitter from the cable company with lower loss than the one I was using. Nothing I've done seems to have an impact. The only thing that seems to have an impact is the time of day.

My two questions: first, what would cause this sort of problem to start only at night? Second, how best can I get this solved, when the problems really would only be detectable during a time when they don't do service calls?

My best guess would be lights - but at least in my apartment, the lighting really doesn't change much between day and night (my apartment is pretty much a cave. )

[RonH]

I had the same issue when I got my hdtv and started watching hdtv over TWC.  They didn't have a clue what was causing it, blamed it on my cablecard (Actually, if I called and told them my line to the house got cut in half by a badger they would blame it on the fact that I use a cablecard).  I only had issues at night, usually on sundays.  They eventually came out and ran a new line.  That seemed to help a bit, but not completely.  Now it seems to be ok, haven't had an issue for a while.

[LoadStar]

You know, someone over on another board pointed out... when I first noticed the problem was, roughly, when we had that first hard cold snap, when we went from 60 to 30 overnight... to which I realized that, yeah, every time I've noticed problems, it's been COLD out. It has nothing to do with the time of day... except that it gets cold at night.

That would explain why the last couple of days, during the day (when it's been particularly nice out) I've had great signal... but at night, when it gets colder, the signal goes all to hell.

Now, the challenge - convincing phone jockey at TWC that cold could, in fact, be a problem with cable. I'm not looking forward to that phone call.

[mhz40]

You know, someone over on another board pointed out... when I first noticed the problem was, roughly, when we had that first hard cold snap, when we went from 60 to 30 overnight... to which I realized that, yeah, every time I've noticed problems, it's been COLD out. It has nothing to do with the time of day... except that it gets cold at night.

That would explain why the last couple of days, during the day (when it's been particularly nice out) I've had great signal... but at night, when it gets colder, the signal goes all to hell.

Now, the challenge - convincing phone jockey at TWC that cold could, in fact, be a problem with cable. I'm not looking forward to that phone call.

Could be many things... maybe a bad AGC module in an amp, or crack in the shielding in the plant near your home.  Like all things in life (besides water:eek: ), the solid aluminum case (or shield) around the cable shrinks as it gets colder.  This can create tiny cracks or cause a problem with a connector and mess up your digital BER.  While your are having digital reception problems, look for diagonal lines in any channels between 70-75.  Lines on analog channels are many times indicitive of free-space (off-air) RF getting into your cable signals inside the coax.
You may want to wait until a cold snap is coming, but a service call would be the perscription here... leakage devices carried by TW techs are quite sensitive and should be able to isolate the leak  (if there is one) regardless of temperature.

[LoadStar]

And sure enough, like clockwork, the problems have gotten worse as the temperature drops outside tonight....

Could be many things... maybe a bad AGC module in an amp, or crack in the shielding in the plant near your home.  Like all things in life (besides water & willies:eek: ), the solid aluminum case (or shield) around the cable shrinks as it gets colder.  This can open tiny cracks and mess up your digital BER.  While your are having digital reception problems, look for diagonal lines in any channels between 70-75.  Lines on analog channels are many times indicitive of free-space (off-air) RF getting into your cable signals inside the coax.
You may want to wait until a cold snap is coming, but a service call would be the perscription here... leakage devices carried by TW techs are quite sensitive and should be able to isolate the leak  (if there is one) regardless of temperature.

Diagonal, or horizontal? I'm definitely seeing horizontal flickering lines between 70 and 75.

[Mark Strube]

Yeah, I've always wondered... why do those 70-75 channels always look so horrible?

[LoadStar]

Well, thankfully I got a good CSR when I called Time Warner today, and she didn't think I was crazy when I said it was caused by the cold. Got an appt. set up for Saturday evening. Thanks, mhz40.

[mhz40]

And sure enough, like clockwork, the problems have gotten worse as the temperature drops outside tonight....



Diagonal, or horizontal? I'm definitely seeing horizontal flickering lines between 70 and 75.

Actually yes; they are horizontal.  Sorry for the mis-information.  They should appear only on two of the channels in the 70's.  It's been so long that I forgot the details, but believe me; you will see a problem if you have one.
I think one is caused by WVTV and the other by WCGV leaking into your cable signals from a loose connector, bad splitter or bad shielding...  Not really sure about the specific offenders... it's fallen into the bucket of useless details for me right now.:confused: