Grey's Anatomy No Voice Track

[okoaomo]

The oddest thing occurred with this recording. After the second to last commercial break, there was no voice track just the music track was playing. In fact I learned that the ambient noise such as people talking in the background is part of the music track. The actors dialogue was muted. This continued for the rest of the program. Of course the commercials worked just fine. Is there an explanation as to what caused this to happen? I would have a hard time believing it is a receiver issue. I have my HR10-250 set to record in Dolby. I even attempted to switch to PCM and it still had the same muted dialogue with the background track intact. What could have caused this?

Kevin

[Sparty99]

Had the same problem, but it was early in the episode. It's also happened a couple of times on Lost. Would love to know what's causing it.

[ClemSole]

We had no trouble with the sound on Grey's Anatomy. The problem you are having could have been caused by the local station you were watching. We recorded it from the East coast network broadcast on channel 386. We live on the West coast.

[newsposter]

during lost i had a fuzzy flicker noise like a loose speaker wire.

[TyroneShoes]

... Would love to know what's causing it.
I think I can answer this one. AC-3 audio is sent with metadata instructing your STB or DVB/ATSC tuner how to downmix the various 5.1 channels to 2.0 audio. It's not really complicated, typically 2.0 left gets a mix of center, left, LFE, and left rear, while 2.0 right gets a mix of center, right, LFE, and right rear. But occasionally the metadata is programmed incorrectly, and 2.0 left gets only 5.1 left, while 2.0 right gets only 5.1 right. Since dialog is typically programmed to the center channel on 5.1, while 5.1 left and 5.1 right typically get only music and effects, the end result is no dialog (or LFE or surround content) in the 2.0 downmix. At least that's usually what happens.

So it's typically a case of your equipment (as well as DTV's equipment) operating exactly as instructed, just with bad instructions from the source, typically due to a simple typo or ommission in the setup.

[jhart1945]

Thanks TyroneShoes for the answer but what is the fix. I have had the same thing happen and it usually lasts for 1-2 minutes and clears up. I have only noticed it when watching high def programming. I have Comcast Cable service. Is this something they would fix or is it a network feed problem.
Thanks in advance

jhart1945

[hybucket]

I think I can answer this one. AC-3 audio is sent with metadata instructing your STB or DVB/ATSC tuner how to downmix the various 5.1 channels to 2.0 audio. It's not really complicated, typically 2.0 left gets a mix of center, left, LFE, and left rear, while 2.0 right gets a mix of center, right, LFE, and right rear. But occasionally the metadata is programmed incorrectly, and 2.0 left gets only 5.1 left, while 2.0 right gets only 5.1 right. Since dialog is typically programmed to the center channel on 5.1, while 5.1 left and 5.1 right typically get only music and effects, the end result is no dialog (or LFE or surround content) in the 2.0 downmix. At least that's usually what happens.

So it's typically a case of your equipment (as well as DTV's equipment) operating exactly as instructed, just with bad instructions from the source, typically due to a simple typo or ommission in the setup.

SOunds good to me, whatever you said.
Happened to me last Sunday for the first 10 minutes of DESPERATE HOUSEWIVES on Boston ABC.

[TyroneShoes]

Thanks TyroneShoes for the answer but what is the fix... Is this something they would fix or is it a network feed problem.
Thanks in advance

jhart1945
Part of my reply indicated that it is not really broken. What I mean by that is that it is usually a configuration problem at the source, and only manifests as a problem at the decoder, even though everything downstream of the problem is working properly. So there really is no fix, and no practical workaround.

Broadcasters as a rule (good broadcasters, anyway) constantly monitor video and audio using equipment and transmit paths similar to what the customers are subjected to, so problems are usually fixed at the source pretty quickly, except that good monitoring becomes more impractical the more streams a broadcaster generates.

But then sometimes it could simply be missing metadata, and not a config issue at all. It could be that the reason we see this so often, and this is purely speculation on my part, is that the default for missing metadata is to map L to L and R to R in lieu of 5.1/2.0 downmix standard protocols. Since L and R from 5.1 typically contain no dialog, a problem such as this then becomes pretty glaringly evident when downmixed to 2.0. If the default were changed so that center defaulted to L and R instead, maybe we could sail through these issues a bit more elegantly, but that sort of change would probably not be likely.

[newsposter]

it always amazes me that employees of the station (on and off duty) aren't watching the station at any given time and call in when stuff like this happens. Heck even friends of employees.

[TyroneShoes]

it always amazes me that employees of the station (on and off duty) aren't watching the station at any given time...
I could tell you some amazing stories that would curl your hair, but this one is actually pretty understandable.

Keeping track of 100 video monitors at once is not easy, but is doable. But monitoring more than one audio source at a time is not practical at all. That means if you have one person (typical) monitoring return audio and video, they have to have a plan to monitor multiple audio paths in shifts or cycles. Many stations have master control operations consolidated, so one guy is minding the store for a few stations (or a few different stores, as it might be). Automation makes that practical, even commonplace.

Since HD has a still comparitively-small audience, and since there is still no ROI whatsoever on HD (virtually no one sells commercial time on local HD), TV stations monitor the SD audio regularly, and the HD either sporadically or not at all. I think there's still no excuse for missing audio for more than a few minutes. The best stations have silence monitor alarms installed to alert the operator if audio is missing.

[Wegg]

This just happened to me in the last 20 minutes or so of the first episode of the new Jericho series. So I guess it isn't something wrong with the Tivo. . . I'll have to try and contact the TV station. :(