I see this on occasion when using my SoundBlaster Pro, and I saw it
often when I was hacking on the sbdsp driver.  This message is printed
when a device posts a DMA completion interrupt and the DMA hardware
indicates that fewer bytes were transferred than were originally
requested by the software driver.

I'm not sure why the SBPro is wont to do this, but it mostly seems
harmless for mono output--for stereo playback/recording, sometimes it
results in the flipping of channels if an odd number of bytes were
dropped!

==John