[mythtvnz] Audio on HDMI NVidia Card

[David Kirk]

Hi,

I spent yesterday upgrading my Mythbuntu box from 11.10 to 12.04.  I
had a few problems that I managed to fix, but I still have 2
outstanding issues with audio.

I have an NVidia GT 520 video card and that plugs in to the HDMI input
on my TV.  My TV has an optical audio cable that goes to the home
theatre system.

01:00.0 VGA compatible controller: NVIDIA Corporation GF119 [GeForce
GT 520] (rev a1)
01:00.1 Audio device: NVIDIA Corporation HDMI Audio stub (rev a1)

After lots of experimentation yesterday I managed to get it to work
with MythTV.  When I watch a recording I seem to be getting sound from
all of the 5.1 channels.  This is good.

When I watch live TV, I only get sound from the centre speaker.  This
is not so good.

Worse luck.  When I load up a web browser (Chromium) and try to watch
a Youtube clip or TV on demand I get no audio at all.

If I run aplay -l I see this.

**** List of PLAYBACK Hardware Devices ****
card 0: NVidia [HDA NVidia], device 3: HDMI 0 [HDMI 0]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 0: NVidia [HDA NVidia], device 7: HDMI 1 [HDMI 1]
  Subdevices: 1/1
  Subdevice #0: subdevice #0

Card 0, device 7 is the one that seems to work.  I can test it with
speaker-test -c 2 -D hw:0,7 and I get this.

speaker-test 1.0.25

Playback device is hw:0,7
Stream parameters are 48000Hz, S16_LE, 2 channels
Using 16 octaves of pink noise
Rate set to 48000Hz (requested 48000Hz)
Buffer size range from 64 to 16384
Period size range from 32 to 8192
Using max buffer size 16384
Periods = 4
was set period_size = 4096
was set buffer_size = 16384
 0 - Front Left
 1 - Front Right
Time per period = 5.639946

I'm getting noise from both those speakers.  I can't seem to get 5.1
sound using speaker-test, but for web audio 2 channels should be fine.

I've been searching all day for something to fix my problems, but I'm
not getting anywhere.  Does anyone have a similar system that is
working for them?  Any ideas how to fix my system?  It used to work in
Mythbuntu 11.10.


Thanks

David Kirk