Re: [Alsa-user] Direct memory write for more than 4 channels

[Bruce <abr...@gm...>]

On 15/07/2014 8:41 PM, Clemens Ladisch wrote:
> Bruce wrote:
>> I’m having difficulty getting more than 4 playback channels to work
>> using alsa callbacks and direct memory write.
> Does it work with aplay?
I know internally aplay uses a polled write, but yes, a good idea to try 
anyway;  I'll see if I can do this. Have to look into aplay options to 
move it away from default output channels, and maybe just test 2 
channels on channels 5 & 6, perhaps.
>> The 1st 4 channels work OK if I use slot ID 1, but 5th and higher do
>> not. Also strange pulsing noises appear on other channels (eg 31,32).
> This sounds like a wrong mixer configuration (if the card has any), or
> a driver bug.

No mixer.

Rather hoping someone won't come up and say 'use a more recent alsa', as 
this definitely won't work; aplay doesn't work even on default channels. 
This later alsa may be a weirdo pulseaudio issue (I've tried disabling 
pulseaudio fully) but have yet to get to the bottom of it. Trying to get 
arch linux to boot, in order to avoid pulseaudio.

-- 
Cheers,
Bruce