Audio Dropout on TWC locals

[P a u l]

 

Originally posted by Pat:
FYI, Dolby Digital does not require a fiber channel, and can be delivered by copper.

I said analog...meaning the red and white RCA outputs....not DD. And yes I do know that DD does noit require fibre. We are sending you 5.1 and not a single fibre wire in the signal path.

[kjnorman]

I was unable to do any exhaustive testing last night but I was able to listing for about 1/2 hour during Leno.
 
I was able to tell some different between the analog L&R outputs and the digital.  The L&R did not appear to suffer the sound "pops" as I described before.  The L&R outputs are not as vivid in sonic clarity as the digital output, so this lack on dynamics make help mask the sound flaws.  With a critcal audiophile ear though, I would say that the analog L&R do suffer with a base noise level and appear to slightly distort (like when an amp is being over driven).  Now I must admit that my sound system is very revealing and with a normal TV you would never notice this.  Overall it sounded acceptable (not great, but acceptable).
 
The digital signal, when it popped would not cause my amp (a Yamaha DSP-A1) to lose its lock - like I had previously thought, the amp's display never changed.  It stayed on its digital input and does not momentarily switch to L&R.  Of course, as the pop only happens for a small fraction of a second, perhaps it is too fast for the display to respond; I do not know.
 
Overall, its was hard to tell conclusively.  I listened to both 504 and 710.  The sound pops only happened in the first 10 minutes of my 1/2 hour test last night on both channels.  During that time the digital feed clearly popped while the L&R feed appeared to slightly distort (difficult to tell it this as the analog equivalent of a "pop").  During the next 20 minutes I did not detect any significant sound flaws on either channel.
 
I'll try to monitor it over the coming week and see what happens.
 
I still do not believe it to be the box, as the digital sound on all other channels is okay.  Clearly if the box was faulty then would this problem not be consistent accross all channels.  I do believe that the cable box's D/A converter helps to mask any deficiency in the digital audio feed, that perhaps my Yamaha does not accept.  

It would be helpful if those who have also said that they get the same type of sound pops, can test their analog L&R connections to determine the results.

Thanks
Kerry

[kjnorman]

Quick update:

Our headend engineer at TW still thinks that this may be a decoder box problem.

They are currently testing at the head end with a demo Pioneer HD decoder box, and have also been feeding back the sound issue problem with Scientific Atlanta to see if there is a firmware fix that can be done remotely.

I have not had any chance to really "watch" much TV in the last few days, but when I quickly tested about 20 minutes worth yesterday I did not experience any problems.  Anyone still getting sound pops?

Kerry

[mr_yeti]

I've been pretty busy this week, but things should start settling down tonight. I'll do some watching and see if I still have problems.

May I assume that we're all using the coaxial digital outputs from our boxes?

[SugarRay]

I had audio 'pops' tonight on 710 and 504.

[kjnorman]

I've got some good news - hopefully.

Got feedback from our headend technican today:

 

I received a reply from SA regarding my inquiry of the audio problem.  Based on a previous case in their database, the fix for the AC3 problem on HD boxes was an OS upgrade (set top operating system).
Low & behold... we are currently planning an upgrade for early morning Tuesday, December 10th.  (Believe it or not, it was on the schedule already!)  I still need to check if the OS as well as the Resident Application will be upgraded.  Obviously I will petition for both.  Will update you after the upgrade is completed.

It will be interesting to see if this fixes our problems post Tuesday.

Kerry

[mr_yeti]

That's great news!

I experienced significant problems with 710 last night, but fell asleep on the couch before I could check 504. 512 was pretty good.

[Gregg Lengling]

Even though I am not a TWC customer I am very happy to hear how well they have responded to the problem...located it and planned for the upgrade to the OS to take care of the problem.  Pretty active service team down there...happy to see response of this caliber.

Gregg Lengling
Chief Engineer and President
Camel Communications, Inc.
Milwaukee, Wisconsin

[kjnorman]

Lastest from TW on the 3100HD update:

 

The firmware upgrade went off without a hitch this morning.  I verified that the new Operating System (OS) version on the 3100HD is now 3.3s7.  I had one of my techs monitor 504 for several hours this afternoon.  Although he had not previously heard the problem, I described what to listen ( & watch) for.  No audio issues were noticed.  Hopefully the upgrade has fixed our issues with AC3 audio...  

and

 

Just tuned to 710 and thought I heard an audio problem.  Looking closely, there were several minor video 'jumps' as well.  It could be the HD demo tape.  It looked like highlights of a college game.
It would be interesting to have users note what video format is in use when sound problems are noticed.  On channel 504 (upconverted SD), there were no sound problems for nearly 2 hours.  On channel 710, (16x9) I thought there were some sound problems yet...  it is quite hard to hear clearly in the noisy environment.
In any event, we will pull in whatever resources are needed to ID and fix this problem as we move forward.

It'll be a couple of days until I am able to properly evaluate this.

If you notice problems in the audio coming from the 3100HD box on any of the TW HD channels can you please note the channel, time and program and I will feed this back to our friendly engineer.

Cheers all!

Kerry

[mr_yeti]

I thought the sound actually got WORSE. 710 had some pretty nasty hiss and crackling, and the sound dropped out several times. I flipped through 504 when they were running SD stuff (I think it was local news), and there was no sound at all. I will do a more scientific and useful evaluation as time allows.

[kjnorman]

Well I only watched two things last night.  HBO HD that had no sound issues but then it never did, and about 15 minutes of Leno with no sound issues.

It'll take some time to see if things have improved.

As to PBS, well, the quality of the demo tapes may be in question.  We really need to test 710 when there is a scheduled HD program such as Tracks Ahead at 4pm or Smart Travels at 6:30pm.  There is also a Jessye Norman (no relation) special at 9pm tomorrow.  Finally it would be interesting to see if their SD widescreen programming has issues - eg Secrets of the Dead on Saturday at 7pm.

Kerry

[mr_yeti]

It was Tracks Ahead I was watching that had the crackling, actually.

Eventually, I just turned it off because the problem was so annoying. That and, well, trains.

Why always the trains? Or boats?

[SugarRay]

Had audio drops on  710 and 504 tonight.

[brewtownska]

I still experienced audio dropouts on 504 during the Wallflowers performance on Leno, and afterwards I checked out PBSHD on 710 and had lots of dropout on their loop (I think the gospel singers were on at that point).

I know earlier we were all told there was an upgrade done over the cable line to fix a known problem with the Scientific Atlanta 3100HD boxes, but does anyone know how to be SURE the upgrade took effect?  I mean, does anyone know how to show the software or firmware versions...a code or some setting that will display that info.  That would at least tell us if TWC's upgrade actually took effect.

Mike

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TWC 3100HD box on both
50" Toshiba 4:3 HDTV &
Sony 1272Q CRT Projector

[kjnorman]

I myself think it has improved.  I do notice the occasional drop, but to me it is now more like a momentary hiss rather than the annoying pop.  This is my experience at least on 504.

I will feedback the results to TW's engineer.

Kerry