[Alsa-user] NVidia GT220 HDMI: routing between PCMs and hardware devices

[Soren H. <sth...@gm...>]

I upgraded to ALSA drivers 1.0.22.1 (in kernel 2.6.34) yesterday to
get HDMI output working on my NVidia GT220.  I upgraded alsa-libs,
alsa-headers, and alsa-utils (Gentoo packages) to 1.0.23.  "aplay -l"
shows four different hardware devices numbered 3,7,8,9 and "aplay -L"
shows a null PCM and an HDMI pcm (alsa-info.txt attached).  The HDMI
is connected to a Sony A/V receiver.

I can successfully play PCM, AC3 and DTS if I route it directly to
hardware devices 7, 8 or 9 (eg, by running "speaker-test -D
plughw:0,7").  If I route the sound to hardware device 3 (eg, by
running "speaker-test -D plughw:0,3"), the sound is badly distorted,
and the receiver behaves as though it's receiving a bad bitstream.  If
I route the sound to the HDMI PCM, then nothing happens; the receiver
shows that it's not receiving any audio data at all.

So I have two questions:

#1: How can I disable or fix hardware device 3?  I have tried using
0xfff and 0xfff2 (each separately and together) as probe_mask options
for the snd-hda-intel kernel module, but these have no effect on which
hardware devices show up.

#2: How can I play sound through the HDMI PCM, rather than routing it
directly to the hardware device?

Thanks.

-- 
Soren Harward