Comment 28 for bug 246969

As far as I can see, this is neither a real problem of the kernel (except that snd_pcsp is so exceptionally low-quality, much worse than we are used to from the good old DOS .mod players :) ), nor in pulseaudio, which just gets presented an ALSA card, but that the snd_pcsp device is not really meant for serious audio playback.

Since there hasn't been any more promising solution so far, I am going with the blacklist solution for now. This can easily be reverted if someone has a better idea.