SPDIF passthru'

[neophyte]

I use an M-Audio Revo 7.1 soundcard. Altho' I understand this to have a fairly good on-board DAC I don't need to use its DAC because I also own a Meridian 561 surround-sound processor (audiophile quality) which can decode pretty-well anything. So all I want/need out of my HTPC is bit-perfect audio, via the Revo's SPDIF socket. I used to be able to get this when playing-back CDs and media files, but since installing DVBViewer (Pro and GE) I can't anymore. Nor can I get digital audio using DVBViewer to watch/play back video or to play back DVDs.

 

All I can now get is analogue audio - via the Revo's line-out socket. I've stared at all my settings 'til I've gone cross-eyed and I can't see anything wrong. I've read the manual forwards backwards and sideways, at least five times, and I still can't see it.

 

Can anyone, please, suggest what might be the cause of the 'missing' SPDIF? In particular, how is it connected with my having installed DVBViewer? Or must I look elsewhere for an explanation/solution?

edit: any more files needed?

Edited March 1, 2006 by neophyte

[danielkoch]

have you configured the ac3filter properly? i have problems with ac3filter and spdif, too. when i want to watch dvd`s with DVBViewer i use Cyberlink Audio Decoder.

[neophyte]

Can anyone, please, suggest what might be the cause of the 'missing' SPDIF?  In particular, how is it connected with my having installed DVBViewer?

Bump. Anyone...?

[neophyte]

have you configured the ac3filter properly? i have problems with ac3filter and spdif, too. when i want to watch dvd`s with DVBViewer i use Cyberlink Audio Decoder.

Hello danielkoch,

 

"Properly?" I'm not sure.

 

I'm using ver. 1.01a (I had problems with the later ver. I tried first). On the 'System' tab I have selected AC3 for AC3 and PES (DVD), and I have specified SPDIF passthrough for AC3, DTS and MPEG Audio. 'Prefer AC3 filter' is ticked and so is 'Use DirectSound as default audio renderer'

 

On the 'Main' tab there's a box saying "SPDIF (disabled)". This is a bit Irish I *presume* that ticking the box disables SPDIF, so I've left it unticked.

 

But, in any case, I'm not sure what (if any) part is played by AC3 when what I'm trying to get (when playing an audio CD for instance, or a DVD) is an audio stream passed out through the SPDIF socket on my soundcard without undergoing any resampling inside the PC. I do have a use for AC3 when using DVBViewer because two of our local channels have AC3 sound; but even then I still want that audio stream to be passed in its digital form via my soundcard's SPDIF connector.

Edited March 7, 2006 by neophyte

[danielkoch]

With "properly" I meant correct

Where did you get Version "1.01a "?

I suggest to use the official version of ac3filter. On http://ac3...ourceforge.net/

the latest Version is v0.70b. On "Main" -> "Output" -> "Speakers" you have to select SPDIF. There`s no box to tick!? (on 0.70b). On "Sample format" use PCM16 Bit.

 

I hope this works for you. If not: Do you have another Audio Decorder e.g. Cyberlink Audio Decoder?

 

Greetings

Edited March 7, 2006 by danielkoch

[neophyte]

...

I suggest to use the official version of ac3filter. On http://ac3...ourceforge.net/

the latest Version is v0.70b. On "Main" -> "Output" -> "Speakers" you have to select SPDIF.

...

I hope this works for you. If not: Do you have another Audio Decorder e.g. Cyberlink Audio Decoder?...

danielkoch

 

If I select SPDIF in ac3 filter I get no sound at all

 

I can't be certain that my sound-card hasn't broken, because I have no way to physically test its SPDIF output independently. But its mixer applet certainly registers output, and it was working perfectly before I installed DVBViewer. But I've had a lot of other problems with this PC since then.

 

I was hoping that one of the experts might be able to tell from the files I uploaded whether or not it is something in the way I have set up DVBViewer that is preventing SPDIF audio from being output from my soundcard. That's why I asked for help in this forum but, so far, none of the Moderators has responded Too busy I guess.

 

(Yes, I have the Elecard audio decoder installed as well).

 

Regards and thanks

[Griga]

how is it connected with my having installed DVBViewer?

 

Quite unlikely that it is connected at all, particularly when DVBViewer is not running. The only kind of interference I can imagine are DirectShow filters that are installed with DVBViewer. Usually they can't influence the audio output of other software, but who knows...

 

Try this: Download the RadLight Filter Manager. Go to the DirectShow section and unregister the following filters:

 

Radlight Audio Select, if present (RLAudioSel.ax)

Dedynamic (dedynamic.ax)

CDDA Reader (cddareader.ax)

Sample Dumper (RLDumper.ax)

 

In case you want to re-register them: The files are located in DVBViewer\Filters.

 

'Prefer AC3 filter' is ticked

Suggests that the AC3 filter causes the trouble, because with this box ticked it will be used for all kinds of audio output. Make sure that "Use for PCM" is unticked, in order to prevent the AC3 filter from being a busybody as audio postprocessor, even if there is nothing to decode (e.g. in case of CD playback).

 

BTW: Did you install codec packs?

[neophyte]

Hi Griga

 

I unregistered 3 of the 4 filters (didn't have RLAudioSel.ax) but still got no SPDIF audio. Then I unticked 'Prefer AC3 filter'; made no difference. To make sure, I unregistered AC3 filter; ffdshow is the filter DVBViewer now uses for AC3 audio instead of AC3 filter. But still only analogue audio. So it seems AC3 filter isn't the cause of the problem.

 

BTW the current version of AC3 filter doesn't have any box saying 'Use for PCM', though the previous version did have such an option.

 

And no, I don't have any codec packs installed. I have installed the 'tools' package of K-Light Codec Pack, but none of the codecs. I also have Real Alternative for streaming audio, with Media Player Classic as my player (for CDs only). When things were working properly previously, I was getting digital audio via SPDIF through this setup. Might there be something clashing between Media Player Classic and one or more filters being used by DVBViewer?

[neophyte]

'Prefer AC3 filter' is ticked

Suggests that the AC3 filter causes the trouble, because with this box ticked it will be used for all kinds of audio output. Make sure that "Use for PCM" is unticked, in order to prevent the AC3 filter from being a busybody as audio postprocessor, even if there is nothing to decode (e.g. in case of CD playback).

 

An afterthought:- Might ffdshow be having the same effect ("being a busybody...even if there is nothing to decode..."), and ought I therefore to unregister that as well?