In a multimedia application I'm using different methods in order to map
a waveOut device to a waveIn device: the first method attempts an exact
match based on the device name, the second method is based on the same
mixer ID and the last one tries to match paritally the device names.
Of course everything is working fine on XP and 2000, but on Vista given
that MAXPNAMELEN is 32 and the playback devices are in form of
"Speakers on (...)", the above mapping methods will fail, because the
device name is truncated.
Another problem on Vista, is with the MM_MIXM_CONTROL_CHANGE
notification message which on Vista is triggered all the time and the
dialog in which I'm using it cannot show up.

Windows Multimedia API issues on Vista
DevDells
CSWong