Re: [Alsamodular-user] Problems on Debian Sarge: Can't connect to ALSA

[Frank N. <bea...@we...>]

Hi list,
Artemiy Pavlov <ar...@kd...> wrote:

> Hello Frank and thanks for you reply. Since I have a similar problem, I am 
> sending you my data.
> 
> This is what I get when I start ams (compiled from source):
> 
> [artemio@localhost ~]$ ams
> QMultiInputContext::changeInputMethod(): index=0, slave=xim
> LADSPA_PATH: /usr/lib/ladspa/
> loadPath: /home/artemio/audio/patches/AMS/, 
> savePath: /home/artemio/audio/patches/AMS/
> Alsa_driver: detected more than 1024 playback channnels, reset to 2.
> ALSA lib pcm_mmap.c:368:(snd_pcm_mmap) mmap failed: Invalid argument
> Alsa_driver: can't set playback hardware parameters.
> Can't connect to ALSA
> 
> Versions:
> AMS 1.8.7
> ALSA 1.0.9

Hm..I checked my own system (AMS 1.8.7 and ALSA still at 1.0.7), and 
surprisingly I get similar results (never noticed this before):

franky@faramir:/u1/src/alsa/ams-1.8.7> ./ams   
LADSPA_PATH: /usr/local/lib/ladspa
loadPath: (null), savePath: (null)
Alsa_driver: detected more than 1024 playback channnels, reset to 2.
Alsa_driver: detected more than 1024 capture channnels, reset to 2.
ALSA device plughw:0,0 opened with 2 inputs and 2 outputs
Can't create ALSA thread with RT priority

However, AMS still does start up fine and works for me, in both ALSA and
JACK mode. That would tell me that:
- The AMS code that deals with ALSA PCM devices is old/outdated.
- The message about the ridiculous number of playback and capture
  channels is wrong, but non-fatal.

So, your problem rather seems to be the message a little later:
> Alsa_driver: can't set playback hardware parameters.

If you start ams with --help, you get its usage, which includes information
about the default settings for various parameters. E.g. AMS uses a hard-coded
default for the sample rate of 44100 Hz. Now, if your soundcard can only
deal with fixed rates like e.g. 48000 Hz, that would explain the error
message. So, try to do:

ams --rate 48000

and let us know if that helps.

Greetings,
Frank