5.1 Surround Sound settings

[poit57]

I have my HTPC set up in my living room running through a 5.1 surround sound receiver. I can't figure how to get Windows Media Center and other media apps outside WMC to play 5.1 surround sound without reconfiguring my default audio device every time I switch between the WMC and the other apps.

Here is what I have found:

I originally set up my computer in another room without the audio receiver. The audio output defaulted to a 2 speaker configuration. When I go through the WMC setup, I selected that I have 5.1 speakers. I test them and it plays sound from all speakers. When I play TV from an HD channel, the receiver indicates that it is receiving a Dolby Digital audio signal and plays through my surround sound speakers as expected.

When I play media outside WMC, like blu-rays through Cyberlink PowerDVD, I noticed that the audio was only playing in stereo because of the default audio setup indicating that I only have 2 speakers. My next step to try to resolve this issue was to reconfigure my speakers in the Windows audio devices settings to indicate that my speaker configuration is 5.1 speakers. I tested the speakers and each of them played sound as expected. Now the third-party apps will play movies with the correct surround sound audio.

The next issue I realize is that Windows Media Center will no longer play audio correctly. When I play a selected recording, the video starts playing, but the audio plays the first second of sound on a repeated loop until WMC generates an error that I need to check my codecs. When I try to reconfigure the audio within WMC again and tell it that I have 5.1 speakers, the test audio never plays, so I cannot complete this setup.

Is this a design limitation that WMC cannot decode the audio when they system is set to a 5.1 speaker configuration? Or is there some other trick to get my computer to output 5.1 audio whether I'm playing media inside WMC or not?

[richard1980]

You had it right to begin with. Windows should be configured to output to two speakers and exclusive mode should be enabled. Then you have to configure each of your applications to output Dolby Digital.

[curtis]

It is a bug with Windows & Media Center when outputting to HDMI that has been there for some time. You can't just "set each of our applications to output to Dolby Digital" as of course many applications (like Media Center) don't have that option for converting the media's non-DD/DTS audio to DD nor do they have ability to use 'exclusive mode'. For example if you have anything with FLAC or other surround sound or you want to play Netflix via Media Center or browser, you are going to get stereo in that setting. Only thing I've found is that will work for all apps is to remove exclusive mode and output to 5.1 PCM (assuming that is your number of speakers) but it is possible the channel mappings get screwed up by Windows as is the case with my Intel HDMI audio.
For the my setup, I currently leave exclusive mode on in stereo settings, run LAV filters to bitstream DD/DTS, and then for non TV content that doesn't have DD/DTS track (almost half of my movies I have on my server), I have to manually switch the windows audio settings to 5.1 and then back to stereo when it is time to watch TV.
List of settings and results here
http://www.thegreenbutton.tv/forums/vie ... =49&t=7074

[Mike88]

I tried turning off exclusive mode because I read that would give instant audio after un-pausing a recording. And it did. Problem is it killed off the 5.1 audio as per my AVR's display. So I went back & enabled exclusive mode.

I thought I'd just check my sound settings for the heck of it. Turns out I have no option to select Stereo vs 5.1 sound as mentioned above. In Windows 7 when I go to Sounds > Playback Devices there are only 2 devices shown, HDMI and SPDIF. The "Configure" box is grayed out if I select either of these. And there is no "Speakers" device even listed therefore there is no way to select Stereo, 5.1, etc.

I thought at one time I had these options but it's been a couple years since I built & configured the HTPC so I'm not really sure what options I had back then. But everything is setup & working properly. FWIW I'm using HDMI for video from a HD6450 video card and SPDIF audio from the mobo, both feeding the AVR.

Any ideas why there are no Stereo or 5.1 options?

PS - I know this is a Windows 8 forum however I've always seen these same settings mentioned in Windows 7. This just happens to be the most recent Surround Sound thread that I found.

[richard1980]

It is a bug with Windows & Media Center when outputting to HDMI that has been there for some time.

I don't understand what bug you are talking about. Can you explain further?

You can't just "set each of our applications to output to Dolby Digital" as of course many applications (like Media Center) don't have that option for converting the media's non-DD/DTS audio to DD nor do they have ability to use 'exclusive mode'.

The OP didn't ask about converting non Dolby Digital audio to Dolby Digital. The OP asked how to bitstream existing Dolby Digital streams in both WMC and other applications such as Cyberlink PowerDVD.

I tried turning off exclusive mode because I read that would give instant audio after un-pausing a recording.

So you don't already get instant audio after un-pausing a recording?

Turns out I have no option to select Stereo vs 5.1 sound as mentioned above. In Windows 7 when I go to Sounds > Playback Devices there are only 2 devices shown, HDMI and SPDIF. The "Configure" box is grayed out if I select either of these.

There is no option to configure the number of audio channels for HDMI and S/PDIF because it is not necessary. The number of uncompressed PCM audio channels supported by an HDMI sink is described in the sink's EDID, which is read by the HDMI source during the HDMI handshake. S/PDIF supports 2 channels of uncompressed PCM audio.

[Mike88]

I tried turning off exclusive mode because I read that would give instant audio after un-pausing a recording.

So you don't already get instant audio after un-pausing a recording?

Turns out I have no option to select Stereo vs 5.1 sound as mentioned above. In Windows 7 when I go to Sounds > Playback Devices there are only 2 devices shown, HDMI and SPDIF. The "Configure" box is grayed out if I select either of these.

There is no option to configure the number of audio channels for HDMI and S/PDIF because it is not necessary. The number of uncompressed PCM audio channels supported by an HDMI sink is described in the sink's EDID, which is read by the HDMI source during the HDMI handshake. S/PDIF supports 2 channels of uncompressed PCM audio.

When un-pausing a recording there is about a 2 second delay before the audio kicks in. I try to pause when it appears there will be a lull in any dialog but that's not always the case.

Oops, a correction is due - the "Configure" box was only grayed out for the SPDIF device & so I was looking at its "Properties". Unfortunately when I went to look at HDMI I just kept plodding along & looked at its Properties also, and I did this a few times. Later on I noticed HDMI did have an active Configure box & it did have Stereo, 5.1, etc. I apologize for the misinformation.

I just changed over to using HDMI for the audio & set Windows > HDMI > Stereo and the AVR indicates it is receiving a 5.1 signal. I did try changing to Windows > HDMI > 5.1 but had a problem. Video played for a few seconds without sound & then up came a Video Error message saying that the files needed to play video were missing & try to restart WMC and/or the PC. Which I did but to no avail.

I'm not sure if I should update the video card driver even though using Windows > Stereo is the way to go. IOW won't be using the 5.1 problematic setting. I've been hesitant to update drivers since the HTPC has been working just fine. That being said maybe a newer driver will eliminate or reduce that 2 second audio delay.

What does Exclusive Mode do? I previously did Google it before un-checking its boxes, but nothing made sense to me when trying to relate to real world applications. Some websites said to enable it & others said not to. But nothing said what it exactly does to the sound. Bottom line is that I should keep it enabled, correct?

[richard1980]

I'm not sure what you mean by "Windows > HDMI > Stereo" and "Windows > HDMI > 5.1". As I previously stated, you cannot configure the number of channels for the HDMI output because it is handled by the HDMI handshake process. Here is a screenshot I found (not at home so I can't take a screenshot of mine right now).



Exclusive mode allows an application to take complete control of the audio device and is required to be enabled before applications can bitstream any encoded audio formats.

[mdavej]

Richard, if you R-click the speaker tray icon, then pick Playback devices, select the active one (Realtek in your case), the press Configure, you get the option to pick Stereo/5.1/7.1/etc.

Mike, Exclusive means only one app at a time can play sound. If you uncheck, then for example, play a youtube video in a browser and play a TV show in WMC, both will play sound simultaneously. If checked, only the first app would play and the second would be silent. I prefer unchecked, but sometimes WMC will raise DRM related errors if it doesn't have exclusive control. I only ran into this when I used to put my PC to sleep. Now that I run it 24x7, Exclusive off works fine.

I didn't realize Exclusive also affected bitstreaming. I'll have to try that. On my system I got very mixed results where I was often unable to bitstream, regardless of this setting. So now, I no longer attempt to bitstream at all and get everything over PCM.

[richard1980]

Richard, if you R-click the speaker tray icon, then pick Playback devices, select the active one (Realtek in your case), the press Configure, you get the option to pick Stereo/5.1/7.1/etc.

That option is only available if the EDID indicates that the sink supports more than one PCM channel configuration. I think in Mike's case, the sink is just reporting 2-channel support, so there's nothing to configure.

The option doesn't change how many channels of audio information can be transmitted to the sink. It just changes how Windows muxes multichannel PCM prior to output. For example, if you have an 8-channel sink but only have two speakers connected, you would select "Stereo", and anytime Windows is told to output a PCM signal that contains more than 2 audio channels, it will mux the audio to 2-channel.

Mike, Exclusive means only one app at a time can play sound. If you uncheck, then for example, play a youtube video in a browser and play a TV show in WMC, both will play sound simultaneously. If checked, only the first app would play and the second would be silent.

That is not correct. When exclusive mode is enabled, applications have the option of taking control of the device, but it is not mandatory. Until an application actually requests exclusive control, sound is output just like it would be with exclusive mode disabled. But once an application takes exlusive control, all other applications are forbidden until control is released.

I didn't realize Exclusive also affected bitstreaming.

If exclusive mode wasn't required, bitstreams would be corrupted by PCM data anytime PCM data was sent.

[mdavej]

Great info. Thanks

[curtis]

It is a bug with Windows & Media Center when outputting to HDMI that has been there for some time.

I don't understand what bug you are talking about. Can you explain further?

You can't just "set each of our applications to output to Dolby Digital" as of course many applications (like Media Center) don't have that option for converting the media's non-DD/DTS audio to DD nor do they have ability to use 'exclusive mode'.

The OP didn't ask about converting non Dolby Digital audio to Dolby Digital. The OP asked how to bitstream existing Dolby Digital streams in both WMC and other applications such as Cyberlink PowerDVD.

1)1)- Speaking to the long standing issue that is the core of his issue. The link I posted is where I've discussed it previously (as has a number of other people): http://www.thegreenbutton.tv/forums/vie ... =49&t=7074
2) That was your quote, not his. I was attempting to point out that this doesn't fix his issue unless the media he was playing was Dolby Digital. If he was playing FLAC or any other multi-channel content setting 'each of our applications to output to Dolby digital" doesn't do anything as it doesn't convert to Dolby and can't bitstream FLAC (and other formats not showing up being supported).