[solved] I hear audio 1s after playback starts - ALSA & ALC888 S/PDIF

Question

Hello,
I run 64bit Arch Linux, my soundcard is a Realtek ALC888 (HDA ATI SB according to alsamixer) and I use ALSA (alsa-lib 1.0.21.a-1).
The back of my computer looks like this:
I have a YAMAHA RX-V596RDS AV Receiver connected to my sound output via a TOSLINK (S/PDIF or Optical Cable) connector.
My alsamixer looks like this (edited to fit small screen):
I used aadebug to get some info about my setup: output
I have two problems with my setup:
1. Whenever I start playback - be it mpd, mplayer, vlc, flash in ff, aqualung or audacity - the playback will start instantly, but I will only start hearing the output when one second has passed. (So I won't hear the first second at all.)
This also happens when I use the RCA Jack to connect my AV Receiver.
However, if I unmute "Front" and increase volume for it in alsamixer and connect my headphones to the light green (stereo) jack output (on top left in photo above) and tell audacity to use hw:0,0 ("ALSA: HDA ATI SB: ALC888 Analog") as output, I will hear the sound in my headphones *instantly* when playback starts.
When I 'mpd next' the same delay of ~1 second will happen. However I noticed that if I pause audio playback sweep (audio editor) and very quickly continue playback, there will be no gap and no 'loss of audio'.
I suspect, that dmix goes into a stand-by state, whenever audio stops. Can I force dmix to have a longer timout or none at all?
2. I can't get Audacity to playback audio together with other applications. mpd and mplayer and flash in ff and vlc will play audio at the same time, but audacity won't. If I start audacity while mpd is playing, there won't even be the option to select "hw:0,1", "iec958", "spdif" or "default". If I use any other device (like dmix), it will play using analog (I can hear it in my headphone).
If I start audacity, then start mpd and then try to playback in audacity (using any of the devices "hw:0,1", "iec958", "spdif" or "default"), I get following error message repeatedly:
Expression 'ret' failed in 'src/hostapi/alsa/pa_linux_alsa.c', line: 1027
Expression 'AlsaOpen( hostApi, parameters, streamDir, &pcm )' failed in 'src/hostapi/alsa/pa_linux_alsa.c', line: 1059
Any one having these problems? Anyone having ideas what the reasons might be?
Thanks
Last edited by qubodup (2010-01-11 17:45:19)

Answer 1

I don't know if this will help but i used to have a similar problem when i switched to musicmanager as my default music player, (i also have the same soundcard)
When connected to my receiver via optical out there would be a initial delay of around a second everytime when playing a new song, although there was no delay through my laptop speakers.
What worked for me was adding esd to my daemons array