Problems with analog audio

[Simlaf]

Hi guys,

I just installed XBMC on Vista SP1. I don't have a digital connection for audio, I use analog to my logitech Z5500.

Whenever I watch a movie in stereo, it works fine, but if I watch something with AC3, then only the stereo speakers and my left rear speaker works. If I watch something that's encode with DTS, then I get a loud hissing sound from all the speakers. It almost sounds like I don't have the proper codecs for ac3 or DTS, yet I can watch the same file in VMC or WMP.

Any ideas?

Also, I have an ATI 2600 Pro, when I'm going through the menu, it loads up my GPU to almost 100%. As soon as I start a movie it goes back down to nomal, but I'm wondering if there's something wrong with my setup.

I'm so GLAD to be back with XBMC! It's by far the best Media center I've ever had!.

Simon

[feerlessleadr]

i too had that problem when i tried to watch a 1080p video with DTS

at least i had zero frame drops in the short time that i was watching the movie

[biddy]

I too have a weird problem with analogue audio. For some strange reason, the center channel on 5.1 stuff is shifted to my rear right speaker. If I play the same films within windows (vlc or mpc) the sound is correctly played through the front center.

Has anyone else had this or know of any reason this could be happening?

For information, I am using the onboard analogue outputs from my MSI P6NGM mothrerboard which is the Nvidia MCP73 chipset with the Realtek HD ALC888 Chip.

I am presuming I've got everything set up ok as Windows itself works.

And I am using the newest build posted here (12332)

Apart from that everything else is superb. Much appreciate the work by the developers here. Finally my pc can (almost) be as good as my XBOX!

[CrazyIvan]

How do you get 5.1 over analog? What connector would you use on your soundcard/motherboard for this?

[biddy]

You use the jack connectors on the motherboard. You hook up 3 of them, 1 for front left and right, one for the rears and one for center and sub. These then go into the phono sockets for 5.1 sound on the amplifier.

As I say, these work perfectly in Media player, VLC and MPC in windows and most work ok in XBMC apart from the center which is strangely shifted.

[Bartapuce]

Same problem described by Biddy here.

Tested with 12332 and 12409 and T3CH 23/03.

Thanks for your work.

[biddy]

I ended up just swapping the Center/Sub and the Rear left/ right cables on the Amp and all is good. Obviously this messes up Windows though but XBMC is great.

[WiSo]

the config is taken from mplayer

[if channels > 2]
SPEAKER_FRONT_LEFT   | SPEAKER_FRONT_RIGHT  | SPEAKER_LOW_FREQUENCY,
    SPEAKER_FRONT_LEFT   | SPEAKER_FRONT_RIGHT  | SPEAKER_BACK_LEFT    | SPEAKER_BACK_RIGHT,
    SPEAKER_FRONT_LEFT   | SPEAKER_FRONT_RIGHT  | SPEAKER_BACK_LEFT    | SPEAKER_BACK_RIGHT   | SPEAKER_LOW_FREQUENCY,
    SPEAKER_FRONT_LEFT   | SPEAKER_FRONT_CENTER | SPEAKER_FRONT_RIGHT  | SPEAKER_BACK_LEFT    | SPEAKER_BACK_RIGHT     | SPEAKER_LOW_FREQUENCY

Don't know why you have swapped channels.

[biddy]

OK, I've been trying to play with this to see if I can fool the channels into swapping inside XBMC but no luck.

I can't find the code as you state so I presume it's changed slightly, the only place I could find it was in Win32DirectSound.cpp as:-

  const int channel_mask[] = 
  {
    SPEAKER_FRONT_LEFT   | SPEAKER_FRONT_RIGHT  | SPEAKER_LOW_FREQUENCY,
    SPEAKER_FRONT_LEFT   | SPEAKER_FRONT_RIGHT  | SPEAKER_BACK_LEFT    | SPEAKER_BACK_RIGHT,
    SPEAKER_FRONT_LEFT   | SPEAKER_FRONT_RIGHT  | SPEAKER_BACK_LEFT    | SPEAKER_BACK_RIGHT   | SPEAKER_LOW_FREQUENCY,
    SPEAKER_FRONT_LEFT   | SPEAKER_FRONT_CENTER | SPEAKER_FRONT_RIGHT  | SPEAKER_BACK_LEFT    | SPEAKER_BACK_RIGHT     | SPEAKER_LOW_FREQUENCY
  };

Now I've tried to move them around to see if it's the placement that it's getting wrong but to no avail.

I also see in the log that Analogue audio is not passed through:-
09:43:32 T:3460 M:644235264 NOTICE: Creating audio device with codec id: 86020, channels: 6, sample rate: 48000, no pass-through

Is there any way to make this pass through so windows can deal with the audio and not XBMC? Or am I barking up completely the wrong tree with all of this?

[WiSo]

I'm really no expert in this but I doubt that analog needs pass through
Win32DirectSound.cpp is the right place to look in and the code in the constructor is mor or less taken from mplayer so I'm lost here on how to proceed since I can't test it either.
It would be great if you could find something.