Problem with AC3 Audio with Imported Videos

[srcurtis]

Hi

I finally took the plunge this weekend and flattened my Sage box.

I only have 2 speakers in my setup which are connected to the regular output on the on-board sound card.

I reinstalled from scratch and even created new wiz.bin and sage.properties files.

I’m Running Sage V3.0.14.50.

Installed the Nvidia PureVideo decoder and DivX Player in addition to Sage and made sure that Windows Media Centre is running also.

I now have most items working but I can’t get AC3 audio to render from known good imported video files (rips of DVD’s). If I play back a DVD from the DVD drive, the audio works fine, but with the imported video version, I get video but no audio.

Originally I had set the Nvidia Decoders manually in both the Video/Audio setup and the DVD setup but have now made sure that the NVIDIA decoders are the default and have now selected Default for each of the video and audio decoder sources.

I have checked the properties of the NVIDIA Purevideo audio setting by accessing the properties via Radlight and also the Media Player Tools, Options, DVD, Advanced pages. If I select speaker test within that, I do hear audio.

I have altered AC3Filter so that it is not the default processor and removed/reinstalled the NVIDIA decoders. I’ve proven that they are the default by using the Microsoft DECCHECK utility.

I am still unable to decode AC3 audio streams when playing pack imported DVD’s and any help would be much appreciated.

Thanks

Steve

[omega]

It's my understanding that the nVidia decoders will not downmix AC3 audio to the analog outputs unless you use Windows Media Player. I use the nVidia decoders myself, but I run my speakers off the SPDIF optical output (nForce2 board), so I just use AC3 passthrough mode. I haven't been able to get AC3 audio to work with imported videos since upgrading to 3.x, but I think that's because AC3Filter is in the way (and broken) and I haven't gotten around to disabling it yet.

[eobiont]

Try replacing the mpegdemux.ax file in the SageTV\Common folder with the one that was released with version 3.0.5 (July 25th is the file date). This has solved all my problems with AC3 audio not playing correctly in Sage. SageTV 3.0.5 was the last version of Sage where audio worked correctly for me.

[David Lawrance]

Originally Posted by eobiont

Try replacing the mpegdemux.ax file in the SageTV\Common folder with the one that was released with version 3.0.5 (July 25th is the file date). This has solved all my problems with AC3 audio not playing correctly in Sage. SageTV 3.0.5 was the last version of Sage where audio worked correctly for me.

Do you have a link? I should know by now, but I guess that I don't.

David

[srcurtis]

Nope, did not help.

Any other ideas?

Steve

[mlbdude]

From the NVidia PureDVD FAQ:

"Help! I don’t hear any audio from my speakers. What is going on?
There are three reasons why you may not hear audio:

Your speakers may not be connected and/or your volume is too low. Make sure the proper cables are connected and the volume is set to a level that you can hear.
S/PDIF mode is enabled but your cable to your external receiver is either disconnected or the receiver is not on. Check to ensure that the proper cables are connected or turn off S/PDIF mode.
You are trying to watch a DVD-Video using an application that is not listed under “Third Party Application Support.” Please view that FAQ for more information."

"What applications does this product work with?
The NVIDIA PureVideo Decoder contains a video decoder and an audio decoder that are compatible with many third party applications. The video decoder is compatible with any third party application that uses Microsoft DirectShow interfaces for accessing decoders. The audio decoder is only compatible with Windows Media Player 9 or higher and Windows Media Center for DVD playback. It will not work with any other application at this time due to requirements from third-party technologies which NVIDIA is actively working to fix. However, you can still configure the NVIDIA PureVideo Decoder to use S/PDIF mode with any third-party application and output audio to an external decoder. Please follow the steps in the “How do I turn on S/PDIF mode?” FAQ."

[srcurtis]

So why does it work (in Sage) when playing back a DVD in the DVD Player, but not a ripped source?

Steve

[mlbdude]

No clue, but I can confirm that I get the same behavior.

[mkanet]

I can confirm that development made changes to mpegdemux.ax in version 3.0.14 to fix another bug with certain .ts files' audio. I already warned them that some imported video's audio were affected by it. Please report this immediately as a bug if you want this fixed before the official retail release of SageTV 3.0 They are already planning to start wrapping things up! They will ask you to supply them a sample .ts file, they will do the rest...

[mlbdude]

OK, I realized I was testing with a DTS only ripped DVD. Playing back a DD ripped DVD over analog worked fine. Even with the NVDVD decoder.