a11y: howto reduce latency with alsa's dmix plugin?

[Halim Sahin <halim.sahin@freenet.de>]

Hello,
Is there a way to reduce latency on audiocard if the dmix plugin is in
use?
I am asking because there is a strange problem with asistive
technologies which are outputing through alsa.
E. G. speech-dispatcher takes almost a half sec to stop the
speech-synthesizer.
If the user navigates quickly through menus, there are simultane outputs
at a time.
(tested with an usb logitech headset, snd-intel8x0 based card,
snd-hda-intel).
The same problem can be reproduced by running mplayer with alsa output
driver and pressing
quickly left/right arrow.
You should hear several samples at a time.

Using an sblive card which doesn't use dmix doesn't have such problems.

Using the dmix plugin should audio much faster to avoid this problem.

Please help!!!
Regards
Halim