asterisk users - Jul 2004 - Sound card troubles with asterisk resulting in no sound

Hi,
I have a redhat 8 linux box with a an X100P and a soundblaster sound 
card.  When I start asterisk I get the following message:
WARNING[65544]: chan_oss.c:238 sound_thread: Read error on sound device: 
Resource temporarily unavailable
And then if I try to call in none of the audio files I have set to play 
in extensions.conf actually play.  When I'm outside of asterisk and try 
playing a sound file it works fine, but when I load asterisk I get that 
error and no audio.  Anyone know what the problem could be?  Thanks.