Hello again,
Your message has motivated me to publish my own PortAudio binding, which provides a simpler, more efficient callback-based interface: http://github.com/mietek/portaudio I tried this, and after rewriting the code a bit, I managed to decrease CPU load by 70-80%, which is not bad for starters. However, I'm getting random segfaults, and I've no idea why.
Here's the modified player module (hpaste kindly rearranged the empty lines for some reason): http://hpaste.org/fastcgi/hpaste.fcgi/view?id=14347 Instead of building a list of samples right away, I use an unfoldr-style generator to fill the buffer, whose initial state is created by mixGenerator, and its stepper function is nextSample. In order to get this working, I renamed your module to avoid conflict with the other PortAudio binding, and I had to change the dependencies in the cabal file to base >= 4 && < 5 because of the exception handling code. There's also some broken MVar-based code to handle the end of the song, you can ignore that for the time being. Gergely -- http://www.fastmail.fm - The professional email service