Hi Lee I'm not sure what the "set_rtlimit problem" is here - I'm a little confused. In terms of what set_rtlimits does, it seems to me that the watchdog thread issue can be easily dealt with: define the max rtpriority value in /etc/set_rtlimits to be X, knowing that the maximum jackd "-P" option value one can use is X-10. Certainly getrlimit()/setrlimit() (which set_rtlimit uses to do its thing) seem to take the current rtpriority rlimit into account. The former also returns the rlimit hard limit for the process, which I interpret to be the "upper limit" mentioned in the original email. In testing I've done during development, set_rtlimits seems to do the right thing, based on my understanding of what the right thing is. If I've misunderstood something though I'm happy to be corrected. Regards jonathan