
Additional documentation for the mixer class and destricption of
class members:

devmask:     All devices being at least output capable (bit mask)

recmask:     All devices, that can be a record source (bit mask)

recsrc:     All devices (again a bit mask!), which are currently record
            source. There can be multiple record sources. Attention: Even
            OSS can have multiple record sources, plain Soundblasters dont
            have, but OSS claims to be prepared for this case.

