http://bugs.winehq.org/show_bug.cgi?id=9358
--- Comment #23 from Raymond superquad.vortex2@gmail.com 2010-04-06 20:14:49 --- (In reply to comment #21)
They are, sort of. Unfortunately alsa dmix uses power or 2 period sizes, and since nobody has hardware mixing I used that function to find out how big a period should be.
the point is the period size of usbaudio is related to USB (URB) packet size
device dmix seem allow you to use any period size/period time , unfortunately use can specified those parameters of the slave pcm of the sound cards in .asoundrc or /usr/share/alsa/cards/*.conf
do you mean that you want to know the actual period size used by hw device ?
To achieve low latency , you have to use small period size but the minimum period size of the sound cards are unlikely to be safe for all users with different cpu speed , different loading