Hello,
My system's ALSA related info is at this link:
http://www.alsa-project.org/db/?f=018a1 ... d05bfaa92b
I am running Knoppmyth R5.5 on an Asus M2NPV-VM motherboard (with ASUS's spdif header installed for optical out).
DTS Passthrough works PERFECTLY via my S/PDIF connector to my receiver and I get a red DTS light on the receiver and beautiful surround sound.
However, I cannot get AC3 passthrough via S/PDIF to work, even though it APPEARS to be working perfectly in Mplayer, Xine, or Mythtv. All I hear is silence, even though the AC3/DD light comes on on my receiver and goes off again when I stop playing a video, and mplayer for example looks happy:
Code:
sh-3.1$ mplayer -vo null -ao alsa:device=spdif -ac hwac3 ./Test\ AC3\ v2.0.avi
MPlayer dev-SVN-r26940
CPU: AMD Athlon(tm) 64 X2 Dual Core Processor 4200+ (Family: 15, Model: 75, Stepping: 2)
CPUflags: MMX: 1 MMX2: 1 3DNow: 1 3DNow2: 1 SSE: 1 SSE2: 1
Compiled with runtime CPU detection.
Playing ./Test AC3 v2.0.avi.
AVI file format detected.
[aviheader] Video stream found, -vid 0
[aviheader] Audio stream found, -aid 1
VIDEO: [DX50] 640x480 24bpp 25.000 fps 159.3 kbps (19.4 kbyte/s)
Clip info:
Software: Nandub v1.0rc2
==========================================================================
Opening video decoder: [ffmpeg] FFmpeg's libavcodec codec family
Selected video codec: [ffodivx] vfm: ffmpeg (FFmpeg MPEG-4)
==========================================================================
==========================================================================
Forced audio codec: hwac3
Opening audio decoder: [hwac3] AC3/DTS pass-through S/PDIF
No accelerated IMDCT transform found
hwac3: switched to AC3, 384000 bps, 48000 Hz
AUDIO: 48000 Hz, 2 ch, ac3, 384.0 kbit/25.00% (ratio: 48000->192000)
Selected audio codec: [hwac3] afm: hwac3 (AC3 through S/PDIF)
==========================================================================
AO: [alsa] 48000Hz 2ch ac3 (1 bytes per sample)
Starting playback...
VDec: vo config request - 640 x 480 (preferred colorspace: Planar YV12)
VDec: using Planar YV12 as output csp (no 0)
Movie-Aspect is 1.33:1 - prescaling to correct movie aspect.
VO: [null] 640x480 => 640x480 Planar YV12
xscreensaver-command: warning: $DISPLAY is not set: defaulting to ":0.0".
xscreensaver-command: warning: $DISPLAY is not set: defaulting to ":0.0".
A: 33.4 V: 33.4 A-V: 0.000 ct: 0.000 835/835 0% 0% 0.1% 4 0
Exiting... (End of file)
sh-3.1$
The above test file is one of many many AC3 encoded files and DVDs I have tried. PCM and DTS works so shouldn't AC3 also work?
I actually am also having a problem with PCM audio: I have to use a custom .asoundrc in order to get audio to not sound "slowed down" when played from my optical out connector. I have to force the sampling rate DOWN to 44100Hz because at 48000Hz all PCM audio comes out "slow" on the receiver. Also, when resampling is disabled, I see mythfrontend giving "buffer underrun" errors in the log files while trying to send the PCM audio out. I am sure this is unrelated to the S/PDIF problem that I am having.
The sound card is the onboard NVidia / AD1986A based GeForce MCP51 HD Audio chip, which uses the snd-hda-intel driver.
It seems like a LOT of people really like this motherboard and so I must be able to get it working for AC3 passthrough, but after months of struggling (literally) I am running out of ideas.
Does anyone have any that I can try?
Regards