Surround sound and audio problems

dave t · 06-10-2010, 06:30

I've noticed increasing problems with audio channels either being dropped out or mixed up lately, to the point of being a real nuisance.

1) Left-rear audio missing or very low. Noticed this increasingly on Channel One/Bravo/Living, but can occur on others such as E4. Interestingly, never on Sky One (audio has so far been perfect on Sky One HD). This occurs on both HD and SD.

2) Front/Rear audio swapped with no centre channel. This happens less often, but mainly affects on demand films and only affects HD content with 5.1 encoding. The most recent being "Date Night (HD)" - can anyone else confirm this film having problems? All the dialogue comes from the rear speakers - off balance toward the right also. This has happened on other films in the past, but I do not recall which ones now. Had to put my amp into 2-channel mode to make the sound tolerable.

3) Audio drop outs. Mostly affecting E4/E4 HD. Recorded and live. Used to be very occasional, but now occurs on 80 to 90% of content at a rough guess. Adverts don't seem to have the problem. It seems like it's E4 messing up, but thought I'd see if anyone else gets this.

These problems have not gone away since I swapped from the SA V+ box to the Samsung one (had an issue with the SA one rebooting/locking).

I have the TV connected directly to the V+ box via HDMI, and a seperate optical audio connection to the amp.

I also do not get this problem from any other audio source, such as my DVD/Blu-Ray player (HDMI) or PC (HDMI+Optical).

Anyone else get any of these problems or similar?

dave t · 12-10-2010, 12:13

Nobody?

dave t · 24-10-2010, 10:49

It's getting worse! Surely I can't be the only one?

The most affected channels are E4 HD, Living HD and Syfy HD.

New to the list of problems is on Living HD, when watching the new series of Chuck, the latest episode had audio on the rear channels ahead of the front by a good 3 seconds, as well as the "usual" off-balance toward the right.

Sky One HD is STILL fault free so I know this is not my setup.

Digital Fanatic · 24-10-2010, 17:03

Quote:

Originally Posted by dave t

It's getting worse! Surely I can't be the only one?

The most affected channels are E4 HD, Living HD and Syfy HD.

New to the list of problems is on Living HD, when watching the new series of Chuck, the latest episode had audio on the rear channels ahead of the front by a good 3 seconds, as well as the "usual" off-balance toward the right.

Sky One HD is STILL fault free so I know this is not my setup.

Sounds like either your set-up or the V+box is faulty. Suggest a full connection check then a call to Support on 151.

dave t · 24-10-2010, 17:55

Quote:

Originally Posted by Digital Fanatic

Sounds like either your set-up or the V+box is faulty. Suggest a full connection check then a call to Support on 151.

Yeah, 151 is my absolute last resort. Wanted to check here to see if anyone else was getting similar issues. Seems not.

It was just the nature of the apparent fault that made me think it was the broadcast signal, not the audio after the box. ie, it doesn't occur on Sky One at all, but does on others. Surely if it was something my end, it would occur on Sky One too?

In the meantime, the recordings have messed up anyway (long deleted programmes are showing up in the recorded list with a date of "NOW"), so I'll be re-formatting this week to see if it helps.

Thanks for replying anyway.

spiderplant · 24-10-2010, 19:48

Quote:

Originally Posted by dave t

it doesn't occur on Sky One at all, but does on others. Surely if it was something my end, it would occur on Sky One too?

It could just be something different in the way Sky encode their audio.

I think it's likely to be your amp at fault. The V+ just passes through the Dolby data, so there isn't any way it could modify the stream in such subtle ways. Also, as you say, you've had the problem with both SA and Samsung V+ boxes. They use totally different hardware and software so it's most unlikely they would have the same fault.

Just curious: does it do it on BBC HD? The "Preview" they show when the channel is off air includes a Dolby test every couple hours. Could be worth recording it as an experiment.

Digital Fanatic · 24-10-2010, 22:13

Quote:

Originally Posted by dave t

Yeah, 151 is my absolute last resort. Wanted to check here to see if anyone else was getting similar issues. Seems not.

It was just the nature of the apparent fault that made me think it was the broadcast signal, not the audio after the box. ie, it doesn't occur on Sky One at all, but does on others. Surely if it was something my end, it would occur on Sky One too?

In the meantime, the recordings have messed up anyway (long deleted programmes are showing up in the recorded list with a date of "NOW"), so I'll be re-formatting this week to see if it helps.

Thanks for replying anyway.

We've had no other reports of this issue though and you've had it for a while. This would rule out at regional headend issue. As SP says, it could be your amp having a problem with the Dolby stereo signal.

Certainly a strange fault

The old recodings coming back is a known bug that we are working on. Reformatting will get rid of them, but it may happen again with another recording until we can roll out the fix.

dave t · 24-10-2010, 23:51

Quote:

Originally Posted by Digital Fanatic

The old recodings coming back is a known bug that we are working on. Reformatting will get rid of them, but it may happen again with another recording until we can roll out the fix.

I don't know if it's useful, but my box only ever has this recording "ghost" issue when the free space reaches critical or very close to critical. Certainly less than 7 hours free seems to do it. Until recently I'd been careful to avoid getting that close, but the other weekend I set all ten of the Star Trek films to record... in HD. Something the V+ box is not actually capable of doing, as it turns out. Roll on the 1TB box!

Digital Fanatic · 24-10-2010, 23:57

Quote:

Originally Posted by dave t

I don't know if it's useful, but my box only ever has this recording "ghost" issue when the free space reaches critical or very close to critical. Certainly less than 7 hours free seems to do it. Until recently I'd been careful to avoid getting that close, but the other weekend I set all ten of the Star Trek films to record... in HD. Something the V+ box is not actually capable of doing, as it turns out. Roll on the 1TB box!

I've got 2 "ghost" recordings on my V+, but I don't think mine got to critical? Yes, can't wait for the Virgin Media TIVO either!

dave t · 25-10-2010, 00:16

Quote:

Originally Posted by spiderplant

It could just be something different in the way Sky encode their audio.

I think it's likely to be your amp at fault. The V+ just passes through the Dolby data, so there isn't any way it could modify the stream in such subtle ways. Also, as you say, you've had the problem with both SA and Samsung V+ boxes. They use totally different hardware and software so it's most unlikely they would have the same fault.

Just curious: does it do it on BBC HD? The "Preview" they show when the channel is off air includes a Dolby test every couple hours. Could be worth recording it as an experiment.

I have seen the sound cutout issue on BBC HD, and I do check those 5.1 tests from time to time. Never seen an issue with those though.

I've done some further investigating, and there seem to be multiple issues appearing as one.

1) The rear left channel issue - I have now confirmed this IS my amp. It was ok on Bluray when I last checked, and had been intermittent on TV programmes, but it is now a 100% dead channel. I have traced this to the switching relay for the rear channels - apparently a common fault after 10 years on the Sony STR-DB930 model. Easily fixed by a solder re-flow

2) The sound cutouts - definitely not the amp. All other sources are 100% ok, and I've even moved the V+ to a different input to compare. When a cutout occurs, the big blue LED that indicates 5.1 surround is being fed to the amp goes out, which means the digital stream is being interrupted. It NEVER occurs during adverts, but can become quite frequent during a programme. I also happens on 2ch stereo programmes, and the display on the amp again indicates a loss of signal.
I've definitely seen other reports on here of the sound cutting out when using optical for audio too. I can't test HDMI because the amp is too old and running it to the TV forces 2ch stereo mode.
I wonder if slight glitches in the data stream from the optical output are confusing my older amp, where a new one might correct the errors more readily?

3) Channel mixups are rare, but are 100% reproduceable on specific content. The latest example I can provide is the film "Date Night HD" on Filmflex. No matter how many times I stopped it and started it again, the dialogue was still not on the centre channel, and instead was mostly coming from the rear channels, with a little from the front two channels. Other 5.1 content (BBC HD etc) was fine as I checked at the time as a test.
Only the dialogue was messed up - the music and background sound was where it should have been.
There have been one or two regular programmes with this issue or similar (Chuck on Living HD last week), but this one is usually films on demand. Most films are fine with no mixups and no cutouts, but a few (I wish I'd noted them all) do it every time.

PBL · 25-10-2010, 06:18

I haven't noticed anything with live content yet, but having recorded alien/s/3 from c4hd a few weeks ago, when playing back the recording i've also seen audio interruptions where the blue dolby light also turns off very briefly.

i'm using the samsung v+ with optical out to a 10 year old sony STR-DE455.

Digital Fanatic · 25-10-2010, 10:30

I wonder if it's the older AV equip having the issue?

dave t · 25-10-2010, 13:11

Quote:

Originally Posted by Digital Fanatic

I wonder if it's the older AV equip having the issue?

That's what I begining to think - it stands to reason that newer kit would more fault tolerant. The problem only seems to exist on the optical output though, having read other threads for the audio cutouts. HDMI seems fine, which suggests that perhaps the fault may lie in the optical output of the V+ box, perhaps in the drivers? Depends how the optical out is driven compared to HDMI.

hedgie · 26-10-2010, 09:00

I have been running a Yamaha RXV-350 for about seven years, although I must admit most my V+ experience has only really seen 2.1 sound as there has been little effective 5.1 content until the recent increase in HD Content. No problems reported from me.

oliver1948uk · 26-10-2010, 09:13

I have an ancient Yamaha DSP AX620 connected by digital audio cable from SA V+ and experience no problems whatsoever except sometimes (particularly between programmes on BBC HD) I have an echo. However, I have found this is because of the effects setting I use on SD channels to make use of all the speakers. If I turn this off on HD channels using true 5.1, all is well and the sound is excellent.

I assume in the settings in the V+ you have HDMI audio override set to ON?