Hi, In my driver I have specified that the hardware supports only two channels. However, if I try playing mono input files on this system I get: Playing WAVE 'test.wav' : Unsigned 8 bit, Rate 22050 Hz, Mono aplay: set_params:1041: Unable to install hw params: ACCESS: RW_INTERLEAVED FORMAT: U8 SUBFORMAT: STD SAMPLE_BITS: 8 FRAME_BITS: 8 CHANNELS: 1 RATE: 22050 PERIOD_TIME: (371519 371520) PERIOD_SIZE: 8192 PERIOD_BYTES: 8192 PERIODS: 4 BUFFER_TIME: (1486077 1486078) BUFFER_SIZE: 32768 BUFFER_BYTES: 32768 TICK_TIME: 0

If I try playing the same file through the virtual device that I specified in asoundrc file like this:

pcm.mydev { type plug slave { pcm default channels 2 } }

and I do aplay -Dmydev test.wav File plays no problem. I guess the question is shouldn't ALSA convert this data automatically or the only way to get this to work is through plugin as I did? Cheers Ogi