[alsa-devel] hda: broken PCM over spdif after AC3; suggestion
Hello,
trying to track down a long standing bug concerning PCM output over spdif and analog ports simultaneously after AC3 passthrough (see https://bugs.launchpad.net/bugs/25632 ), I've been digging into the inner workings of HD Audio...
It seems to me that after playing DVDs with AC3 passthrough the stream associated with the default alsa device is only connected to the front Audio Output widget but not at the same time to the Digital output widget, as I would have expected. I've attached the contents of /proc/asound/Intel/codec#0 during music playback to this mail; you can see the different streams connected to nodes 0x02 and 0x03.
I'm not familiar with the hda driver, but I suspect that after AC3 passthrough the multi-out configuration isn't reset to what it's supposed to be.
Is there a way to work around this issue, or am I completely missing the point?
Thanks for your help, Tomas
At Tue, 21 Oct 2008 02:37:28 +0200, Tomas Cernaj wrote:
Hello,
trying to track down a long standing bug concerning PCM output over spdif and analog ports simultaneously after AC3 passthrough (see https://bugs.launchpad.net/bugs/25632 ), I've been digging into the inner workings of HD Audio...
It seems to me that after playing DVDs with AC3 passthrough the stream associated with the default alsa device is only connected to the front Audio Output widget but not at the same time to the Digital output widget, as I would have expected. I've attached the contents of /proc/asound/Intel/codec#0 during music playback to this mail; you can see the different streams connected to nodes 0x02 and 0x03.
I'm not familiar with the hda driver, but I suspect that after AC3 passthrough the multi-out configuration isn't reset to what it's supposed to be.
Is there a way to work around this issue, or am I completely missing the point?
I didn't check the launchpad page yet, but did you set "IEC958 Default PCM" switch off? Or, start AC3 stream first, then analog stream.
The "IEC958 Default PCM" switch determines whether the SPDIF stream is assigned to the "default" PCM or not.
Takashi
Am Dienstag, den 21.10.2008, 08:32 +0200 schrieb Takashi Iwai: [...]
I didn't check the launchpad page yet, but did you set "IEC958 Default PCM" switch off? Or, start AC3 stream first, then analog stream.
The "IEC958 Default PCM" switch determines whether the SPDIF stream is assigned to the "default" PCM or not.
Thank you for bringing me on the right track! Due to my using an old driver there is no "IEC958 Default PCM" switch, but a little research discovered that you've dealt with this problem in February already (see http://thread.gmane.org/gmane.linux.alsa.devel/50989/focus=51486 ), and the proposed solution to set defaults.pcm.dmix.format S16 in ~/.asoundrc works for me.
I'm going to update the drivers anyways, but I'm confident that it will work now :-)
Again, thank you for your quick response! Tomas
participants (2)
-
Takashi Iwai -
Tomas Cernaj