Hmm very tough one..The only thing I can think of off the top of my head is the timing. If your compression is good, thats all I can think of. You may be able to solve this issue at this other forum. Its more active for Probes and dedicated to Probes
http://forums.probetalk.com
If posting another forum is against the ToS, to any mod, I do apologize, as all Im trying to do is help the man as I am a Probe owner myself.