snd_hda+MCP7A+HDMI= sound silence

[Ildar D. Belkin]

Hello.

I am using ASRock A330ION based on MCP7A-ION Chipset. It has pcm0(analog),
pcm1(digital) and pcm2 HDA NVidia MCP7A HDMI PCM #0 Digital. It has
recognized as well by SND_HDA driver but I cannot switch sound to pcm2(via 
HDMI).
I've read a lot of Internet terms and posts but I cannot search any way to
resolve the problem.
FreeBSD 8.1#amd64 with the latest updates is installed on A330ION with
working sound via Analog port pcm0.
I've tried sysctl hw.snd.default_unit=2 (HDA NVidia MCP7A HDMI PCM#0 Digital) 
and cat /dev/random > /dev/dsp but
sound was turned off from pcm0 (Analog output) and not switched to
HDMI output.
Nothing any errors occur during sound output via pcm2 - only silence.
Video is working through HDMI with nVidia driver.
The cable is garantee working and complain with HDMI 1.3. Also I have tried to 
install Ubuntu 10.04 to check. Sound works with HDMI-port with Ubuntu. 


What need I do to get sound work with HDMI-output (pcm2) with snd_hda and 
MCP7A-ion chipset.


Ildar Belkin