[Intel-gfx] Problems with HDMI audio on Intel DG45FC motherboard

David Härdeman david at hardeman.nu
Wed Oct 21 00:37:58 CEST 2009

On Tue, Oct 20, 2009 at 09:26:00AM +0800, Wu Fengguang wrote:

>Sorry for the long delay!

No problem.

>On Thu, Oct 15, 2009 at 01:40:53AM +0800, David Härdeman wrote:
>> ii) Is there any documentation somewhere on how this mapping is supposed 
>> to be performed in user space?
>I think Shane has provided a good example for you in another email :)
>Here are more descriptions for the route plugin:

So perhaps I should still file a bug with the ALSA bugtracker asking for 
the default ALSA userspace to include a channel mapping along Shane's 

>> >Complete silence for how much time?
>> For the entire duration of the particular movie/audio track/video 
>> clip/whatever.
>I actually have a DG45FC box and have not run into this problem for
>all the HDMI monitors I have. What's your monitor model?

A Samsung LE-55A956 LCD TV. But I think the problem is not with the 
monitor (TV) but rather with the receiver that is between the DG45FC and 
the TV. The receiver is a Marantz SR8002 with HDMI support.

>Did the kernel emit some error messages?


>What if you change display
>modes with xrandr?

Haven't tried that yet...currently running on 1920x1080 at 60 which should 
(I guess) be one of the most common modes with modern LCD TV's.

>HDMI codec/sink seem to take some time to response to the output
>enable and new infoframe, so there are some delay. I've moved the HDMI
>output enable command to module load time, this helps. The infoframe
>is in theory created in run time based on the format of _each_ new
>audio stream, so infoframe transmission has to be started/stopped
>for each track..

So my current theory is along the line of HDMI audio infoframe or video 
infoframe problems. Do you have any pointers where in the driver(s) 
the infoframes (both audio and video) are generated so that I can add 
some debugging statements to dump the frames and compare the working 
and non-working scenarios?


More information about the Intel-gfx mailing list