From: alsa-devel-bounces@alsa-project.org [mailto:alsa-devel- bounces@alsa-project.org] On Behalf Of Jaroslav Kysela

On Fri, 12 Jun 2009, Steve Langstaff wrote:

...

Hi All.

I've got an installation of ALSA (1.0.19 on an embedded device) where

using

...

plug and dmix as my output device slows down playback - voices and

tones are

...

lower in pitch and the playback takes longer than when not using

plug:dmix,

...

e.g.

Does 48000Hz 2 channel source work OK with direct device (without dmix) for your hardware?

Yes, I converted the original sample to 48000 Hz, Stereo, and it sounds OK when I don't use dmix.

/mnt # time aplay -v ignition48000s.wav Playing WAVE 'ignition48000s.wav' : Unsigned 8 bit, Rate 48000 Hz, Stereo Plug PCM: Linear conversion PCM (S16_LE) Its setup is: stream : PLAYBACK access : RW_INTERLEAVED format : U8 subformat : STD channels : 2 rate : 48000 exact rate : 48000 (48000/1) msbits : 8 buffer_size : 24480 period_size : 2040 period_time : 42500 tstamp_mode : NONE period_step : 1 avail_min : 2040 period_event : 0 start_threshold : 24480 stop_threshold : 24480 silence_threshold: 0 silence_size : 0 boundary : 1604321280 Slave: Hardware PCM card 0 'LM4549' device 0 subdevice 0 Its setup is: stream : PLAYBACK access : MMAP_INTERLEAVED format : S16_LE subformat : STD channels : 2 rate : 48000 exact rate : 48000 (48000/1) msbits : 16 buffer_size : 24480 period_size : 2040 period_time : 42500 tstamp_mode : NONE period_step : 1 avail_min : 2040 period_event : 0 start_threshold : 24480 stop_threshold : 24480 silence_threshold: 0 silence_size : 0 boundary : 1604321280 appl_ptr : 0 hw_ptr : 0 real 0m 3.02s user 0m 0.07s sys 0m 0.02s