[PD] Linux newbie, alsa problems

[Frank Barknecht]

Hallo,
David NG McCallum hat gesagt: // David NG McCallum wrote:

> I'm trying to migrate my system to Linux and I'm running into some 
> problems. RH9, Alsa 1.0.0rc2, M-Audio Quattro.
> 
> I configured PD with --enable-alsa and compiled it. But when I do a 
> -listdev I'm presented with "OSS Devices".

listdev does not list alsa devices, but that doesn't mean you cannot
use alsa devices.

> Does then mean the Pd is using the OSS emulation in Alsa, is it using 
> alsa at all? What's going on ?!
> 
> The quattro does more or less work with alsa in xmms and one of the OSS 
> Devices does send sound out of the quattro in Pd. But is it through 
> alsa, or what?

THis can get a bit tricky, but it will be easier, when Miller will
reintrocude the option to select alsa devices by name. Here's the
rundown: 

To use alsa, you should start Pd with the "-alsa" flag. You also can
select the card to use by "-audiodev X" where X is the card number
starting from 1. These options are also available in the "Media" menu.
Miller intends to also add a -alsadev or -alsaadd option again later.

This doesn't really work well with the Quattro. For the Q. you should
first install a so called asoundrc file. You can find it on
alsa-project.org/doc => Maudio => Quattro, or I could send it to you.

This defines several virtual PCM devices that map to different
configurations on the Quattro. The ones to try are called "q4" and
"q4b". But you cannot use these directly with Pd currently, unless you
patch the s_audio_alsa.c file like I described on pd-dev or wait a
moment, until the next Pd version.

Even then, I didn't make it to have both inputs and outputs available
with the Quattro in 4-channel mode, yet.

Here I have another strange problem. Whereas I can use Pd with the
Quattro in my homebox just fine, Pd on my laptop will crickle and
crackle in regular intervals unless I set the buffer to "-blocksize
2048", which is quite a bit of latency. 

Does someone have an idea, where this could come from?

ciao
-- 
 Frank Barknecht                               _ ______footils.org__