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

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

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

> thanks very much for your will to investigate in the problem.
> 
> Please let us know if you have any success.

For a start, I asked Fons Adriaensen about his opinion - I'm quoting a mail
from him:

>> on the alsamodular-list people seem to be having problems with "current" ams
>> (1.8.7), specifically clalsadrv. Here is such a case:
>> ...
>
>I've had similar feedback from several users.
>
>There are two issues here:
>
>First, the  "Alsa_driver: detected more than 1024 playback channnels,
>reset to 2." is nothing new. There is a similar message in jackd:
>"You seem to be using the ALSA 'plug' layer...bla bla". The simple
>fact is that ALSA's plug layer tells the user it provides something
>like 2^16 channels, so in the absence of any correct info, all you can
>do is assume there are at least 2, and continue using that number.
>
>The second problem is more serious. Recent distros / ALSA versions
>seem to use a default 'plug' device that does not support mmap'ed
>access. Since alsadrv uses mmap'ed access (as does JACK), using
>this device will fail for JAAA, JAPA, Aeolus, and also for AMS.
>And while the packagers usually set up JACK to use a hw: device,
>they don't do the same for AMS.
>
>So the solution is to use the hw: devices directly. This can be
>put into the AMS configuration file, and it really should be the
>default. It was at some time until Matthias or SuSE changed it.
>
>I'm quite fed up with the state of affairs with ALSA. If it
>provides mmap'ed access, it should do this on *all* devices,
>otherwise it's useless. In particular on 'plug' devices it
>should be trivial to do so, as these are all software and the
>samples are already in memory anyway.

So, this would indicate that you should try to do
$ ams --soundcard hw:0

(possibly coupled with the earlier mentioned "--rate 48000") and see if
that helps.

Does that improve things? You might also have to check if you have a
.asoundrc in your home directory that modifies which ALSA device is
used by default (though the --soundcard switch should overwrite such
a setting).

Frank