loss of audio

WinXP
Latest max, Jitter, java

fellow patchers.
I have a (to me) unusual problem: when loading the system I can work
with both my Edirol audio interface, built-in audio over asio4all or the
mme drivers.

However, after a while, usually while unlocking a patch, I loose all
audio output, and I must restart to regain control over the audio
system. The patch, for all intents and purposes continues to work,
logic-wise, that is; the Max part, if you will.

This hasn't always happened like that, only after a recent registration
of maxMSP/Jitter on it - in other words, it worked before the authorisation.

Any clues as to what is going on? Are there prefs that I can delete to
get going again?

thanks,
Andreas Wetterberg