[linux-audio-user] Stuttering via HDSP, Cardbus, Multiface?

[Timothy Polashek]

Hello!

Has anyone experienced stuttering and very slow playback via RME 
multiface, cardbus, and Alsa on a notebook, or other computer?  I am 
using the CCRMA low latency kernel on Fedora.

How can I fix it?

My machine has is 2.8 Pentium 4, plenty of horsepower, and two pcmcia 
slots (only one works with hdsploader for some reason).

I know that I have alsa installed correctly because when I modify the 
modules.conf file to use the internal sound card and speakers, 
everything is very fine playing audio back via xmms, audacity, 
csound(from the command line), and pd.

However, once I switch over to the hdsp in the modules.conf file, 
everything runs but extremely slow...  Audacity will take a minute to 
launch and then will play back a 2 minute file over 5 minutes, the sound 
out of the multiface is stuttering and distorted.  (Very beautiful in a 
twisted sort of way!)

My guess is that the problem is the pcmcia bus is somehow 2000 times 
slower than it should be..  csound seems to confirm this hypothesis from 
the command line when attempting realtime synthesis:


$ csound -d -o devaudio toot01.orc toot01.sco
Using default language
0dBFS level = 32767.0
Csound Version 4.23f03 (Nov 18 2003)
orchname:  toot01.orc
scorename: toot01.sco
orch compiler:
32 lines read
sorting score ...
        ... done
Csound Version 4.23f03 (Nov 18 2003)
displays suppressed
0dBFS level = 32767.0
orch now loaded
audio buffered in 1024 sample-frame blocks
hardware buffers set to 2048 bytes
writing 2048-byte blks of shorts to devaudio
 
SECTION 1:
ftable 1:
new alloc for instr 1:
/dev/dsp: could not write all bytes requested
/dev/dsp: could not write all bytes requested
/dev/dsp: could not write all bytes requested
/dev/dsp: could not write all bytes requested
/dev/dsp: could not write all bytes requested
/dev/dsp: could not write all bytes requested
 
[1]+  Stopped                 csound -d -o devaudio toot01.orc toot01.sco

Thanks for the help!

-Tim