This patch greatly improves quality of audio output on my Sparcstation 
20. It also contains some other fixes and improvements.

A full list of changes:
- [audio.c] Added missing semicolon when debug information is enabled 
(compilation bug).

- [audio.c] Number of input and output 8KB buffers is now a module 
parameter as previous authors requested. More buffers should help on 
slower machines.

- [audio.c] Fixes some debug strings, so compilation warnings are gone 
(when debug is enabled).

- [dbri.c] Added missing dbri_get_formats() function, so sox/play now 
plays sound files without forcing it to Sun audio output interface (OSS 
works).

- [dbri.c] Enabled burst transfers for DBRI.

- [dbri.c] Added a fix to not leave few bytes in a next memory chunk 
when building chain of output data buffers for DBRI. It is really a 
critical thing if the next change is applied.

- [dbri.c] [the most important one] Writing an output data (playback) 
returns immediately which allows audio player to prepare next data when 
an audio codec is playing the previous. It removes clicking noise on 
output signal.

I tested  it on dual SuperSPARC 60MHz CPU (OGG file playback = 50% usage 
of 1 CPU).
I am interested in feedback about audio quality change on machines of 
different speed.

Regards,
Krzysztof Helt