[PlanetCCRMA] Some basic FC3+Audio questions

Brian Panulla brian@plutonian.com
Tue Feb 8 11:02:02 2005

Hi all... been lurking here for some time, but I've finally taken the 
plunge and set up a PlanetCCRMA system. I've been working with UNIX and 
Linux for about 13 years, but virtually all of that has been as a 
sysadmin via the command line or in plain old X. Using Linux as a 
desktop workstation with multimedia hardware is still a little foreign, 
so I'm thankful something like PlanetCCRMA exists!

I'm generally having problems playing audio from the CCRMA apps. I'm 
thinking this is because of a lack of understanding on my part of how 
Alsa, JACK, and the non-Alsa apps/systems interact. Since these issues 
seem to cross application boundaries, I thought I'd ask here first... if 
there's something afoot that I need to research elsewhere, pointers 
would be appreciated.

I'm running Fedora Core 3 on a Sony Vaio A250 notebook using the Intel 
chipset audio. My adapter is listed under the Gnome Soundcard Detection 
control panel app as "Intel Corp. 82801DB/DBL/DBM ... AC'97 Audio 
Controller using module snd-intel8x0. I DO hear the sample sound when I 
click "Play test sound" in Soundcard Detection.

I've installed the "stable" low latency CCRMA kernel (2.6.10-2.1.ll) and 
tuned my hard disks as in the instructions. I've also run chkconfig to 
get alsa to start on boot.

I've had a hard time getting audio CDs to play in XMMS. I did some 
digging and found that it was likely my CD drive did not support analog 
audio transfer, so I installed the cdread module for XMMS. I couldn't 
get any audio out of the CD until I played the test sound in my Gnome 
control panel. After that, CD audio plays fine. Does this make sense? 
Does playing the test sound load some module or start some service that 
is required for xmms?

When I fire up qjackctl I am able to start JACK, though it complains 
about not being able to find the realtime capabilities of the kernel. I 
couldn't find any documentation on qjackctl... what does the "RT 0.24%" 
next to "Started" mean? is that an indication of latency performance?

Finally, I tried out Ardour. If I create a simple session, I can see the 
levels on the Ardour mixer react to my microphone, but when I record 
something, I can't seem to play it back. Am I missing a step here?