query    - just queries the driver characteristics
playback - encodes two sinusoidal waves (if output set to stereo) of
           arbitrary frequency and amplitude and continuously writes
           the buffer. It also lets you choose all of the format settings.
play_sleep - sleeps while waiting for the buffer to get empty.

play_mmap - DMA sound.

record   - continuously reads a buffer. It also lets you choose all of the
	format settings.

It's very easy to notice problems with sound and gives you great control
over sound format. Hope you find it useful, and of course improvements are
welcome.

Rui Sousa <rsousa@grad.physics.sunysb.edu>
