LAV Filters - DirectShow Media Splitter and Decoders

[Mevunky]

Originally Posted by raymondjpg

I think you have a point, but in my system it only works if I configure Intel Display Audio in Windows as stereo. I can then get sound out of the center speaker as well as L and R. However, if I configure it as 5.1 surround then the signal received by the Yamaha is 3/2/0.1 even when the source is stereo PCM, and I hear no sound from the center speaker. I have seen this issue arise with other media players outputting HDMI sound through AV receivers. The receiver is expecting to receive signal from all channels, and does not apply Prologic II.

This makes sense, however I see no reason to set Windows to anything other than stereo mode, for proper surround everything is bitstreamed anyway. I have always set all machines to 2.0 as 99% of generic sound content is 2.0 which keeps everything in check and fixes your PL issues - as for the rest its bitstreamed and bypasses the shared mixer anyways. I personally see no upside in setting Windows to anything other than 2.0.

[raymondjpg]

Originally Posted by Mevunky

This makes sense, however I see no reason to set Windows to anything other than stereo mode, for proper surround everything is bitstreamed anyway. I have always set all machines to 2.0 as 99% of generic sound content is 2.0 which keeps everything in check and fixes your PL issues - as for the rest its bitstreamed and bypasses the shared mixer anyways. I personally see no upside in setting Windows to anything other than 2.0.

I'll certainly try setting Windows to stereo mode, but my priority is to try and work around loss of audio when using MPC-HC and display rate switching with madVR. Otherwise I'm limited to using PotPlayer.

The problem I see with setting to stereo is playing back multi-channel AAC. I haven't found an AV receiver yet that will decode AAC sound so the only option is to decode using LAV audio, ffdshow, or AC3 Filter and (if AC3Filter is set for transcoding PCM to AC3) transcoding on the fly. I don't know how Windows and the receiver would cope with multi-channel PCM, if Windows was set to stereo only mode and AC3 Filter (and/or ffdshow) was disabled.

[raymondjpg]

I had another go at setting MPC-HC 1.8.4 as the external player in Emby Theater, this time with the Exclusive mode checkbox selected under Audio Renderer.

1. With audio output set to Default DirectSound Device, behaviour as before. Sound does not survive madVR refresh rate changing.

2. With audio output set to Internal Audio Renderer, sound does survive madVR refresh rate changing. However, it appears that AC3Filter's automatic association with post-processing MPC-HC sound is lost because stereo PCM (now received at the Yamaha receiver as stereo) was not transcoded to AC3. This would not matter too much if the only PCM we wanted to transcode was stereo. I think it might matter more if we wished to transcode multi-channel PCM.

3. Setting AC3 Filter as a preferred External Filter in MPC-HC, E-AC3 (at least) appeared to be decoded to PCM i.e. no longer bitstreaming as desired.

It may be that I have just not found the correct combination of settings. I may try again, but for now I have returned to PotPlayer and external LAV filters.

Edit: On closer scrutiny, it appears that AC3Filter's automatic association with post-processing MPC-HC sound is NOT lost when audio output set to Internal Audio Renderer, and after madVR refresh rate changing. However, the audio delivered to the AV receiver is PCM sound until video play is stopped then started again. Same with E-AC3. After madVR refresh rate changing, the audio delivered to the AV receiver is PCM sound until video play is stopped then started again.

This is not as bad as no audio after refresh rate changing, but I would still prefer to see the correct audio format delivered to the AV receiver after refresh rate changing.

[Mevunky]

Could you not avoid multi-channel AAC content entirely? It is not a great way to do surround (hence why no receivers support it) this would go a long way to solving your problems.