Problems playing certain wav files

David Kelly dkelly at
Thu Jul 3 09:58:35 PDT 2003

On Thursday 03 July 2003 09:39 am, Jason Andresen wrote:
> This almost sounds like another face to the "end of the sound is
> clipped" problem that Newpcm has always had.  It used to be that on
> very small files (interface sounds and whatnot, you just wouldn't
> hear anything.  I guess the new card sends an interrupt back when
> it's done playing the sound or something that tells FreeBSD that it
> can let the program using the soundcard finish shutting down.

I have been bit by the problem described above. Found that I couldn't 
trust the "close sound device when finished" routine. Or maybe it was 
the "is buffer empty and ready for more?" In any case, writing the data 
to the sound device and knowing there were X samples at Y rate the 
device was safe to close after X/Y seconds and no sound was lost.

OTOH an Aureal 8810 using /usr/ports/audio/aureal-kmod always lost the 
first 250 ms or so of sound written to it after opening.

Back to the immediate topic at hand, playing .WAV files. Not all .WAV 
players are equal. The .WAV format defines the playback parameters in a 
header, but there may be many segments in the file where the parameters 
change, or not change. Multisgements are not wildly common so many 
players don't know how to handle it. See wavplay and waveplay in ports, 
one does, the other doesn't.

In short, I suggest installing both wavplay and waveplay. Then play the 
problem .WAV file with each and see what happens.

David Kelly N4HHE, dkelly at
The human mind ordinarily operates at only ten percent of its
capacity -- the rest is overhead for the operating system.

More information about the freebsd-multimedia mailing list