View Full Version : [ubuntu] Some sound over HDMI

August 25th, 2009, 10:36 PM
I recently purchased an ASUS EN9500GT video card to add to my Mythbuntu system. I cannot get multi-channel sound over HDMI. I can run the following command and hear 2-channel stereo sound:

$ speaker-test -Dplughw:0,0 -c2

But if I change that to 6 channel or anything else, I get nothing. Using the mobo (ASUS M3N78 PRO) onboard HDMI out previously, I was able to get 6-channel, DTS or DD.

alsamixer is not muted.

Output from aplay -l:

**** List of PLAYBACK Hardware Devices ****
card 0: NVidia [HDA NVidia], device 0: ALC1200 Analog [ALC1200 Analog]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 0: NVidia [HDA NVidia], device 1: ALC1200 Digital [ALC1200 Digital]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 0: NVidia [HDA NVidia], device 3: NVIDIA HDMI [NVIDIA HDMI]
Subdevices: 1/1
Subdevice #0: subdevice #0

Output from aplay -L

HDA NVidia, ALC1200 Analog
Default Audio Device
HDA NVidia, ALC1200 Analog
Front speakers
HDA NVidia, ALC1200 Analog
4.0 Surround output to Front and Rear speakers
HDA NVidia, ALC1200 Analog
4.1 Surround output to Front, Rear and Subwoofer speakers
HDA NVidia, ALC1200 Analog
5.0 Surround output to Front, Center and Rear speakers
HDA NVidia, ALC1200 Analog
5.1 Surround output to Front, Center, Rear and Subwoofer speakers
HDA NVidia, ALC1200 Analog
7.1 Surround output to Front, Center, Side, Rear and Woofer speakers
HDA NVidia, ALC1200 Digital
IEC958 (S/PDIF) Digital Audio Output
HDMI Audio Output
Discard all samples (playback) or generate zero samples (capture)

Running mplayer on the command line, everything looks good. No errors, finds the correct codecs, etc.

I was just able to run a DD test through the iec958 & surround51 device (from aplay -L). Running the DTS test through the same devices produces static. Using the HDMI device produces silence.

asound.conf just has the following line:

defaults.pcm.device 3

I'm running out of ideas but I'll continue to search. Any help would be appreciated.


ASUS M3N78 PRO mobo
ASUS EN9500GT video card
Mythbuntu 9.04 64-bit
nVidia 180.44
Alsa 1.0.20
Kernel 2.6.28-15

August 26th, 2009, 06:43 AM
Ok. Some persistence has paid off.

I first upgraded to NVIDIA's 185.18.36 drivers. I had to uninstalled Mythbuntu's 180.44 kernel modules to make that work. I tested it with my onboard video card and it worked.

Still no sound w/ the 9500GT.

I then began to follow this thread:


Installing one of those packages changed something because I was able to run DD & DTS test successfully over iec958.

Next, I took a stab at my asound.conf file. I searched for "asound.conf" and "iec958". The first result yielded this page http://www.mythtv.org/wiki/Intel_HD_Audio_-_Realtek_ALC88x. So I tried their asound.conf setting at the bottom of the page and now I can play MP3 files via mplayer!

My asound.conf file now looks like:

pcm.!default {
type plug
slave {
rate 48000
pcm "spdif"

Now I just need to figure out my MythTV settings and I'll be happy.

w00t! Just figured them out! And now I have DD w/ OTA HDTV! And reasonable sound levels! My sound use to be incredible low and I'd have to crank up the volume on my receiver.

My settings:

Audio output device: /dev/adsp (I tried almost all of them!)
Passthrough output device: ALSA:iec958:{ AES0 0x02 } (not sure if it's necessary)
Enable AC3 to SPDIF passthrough (YES!)
Enable DTS to SPDIF passthroug (YES!)

I'd rather run the current NVIDIA driver's available w/ 9.04, but oh well. Maybe I'll try backing them out. I'd hate to undo something that works.

Ok. Time for bed.