[LAD] some questions about writing a jack client

[mutil]

hello everyone,
	I am trying to write a c++/qt4 jack client which mix 2 inputs and has a jack 
output. The problem is that currently jack gets zombified too often and I would 
like some info on how can I debug the exact reason this happens. I suspect 
it's the way the app is written and I am planning to rewrite it but I need 
some advices first.
	The way it's currently written makes use of mutexes and locks to pass the 
data beetween a custom global buffer. Is this the reason for not synchronizing 
good enough and zombifies jack or it's something else that screw things? Should 
I use a ringbuffer (which, to my understanding is lock-free and doesn't need 
mutexes) to get the work done, and if so, are there any jack2 example of this 
or some hints for what I should be aware of? Or have I misunderstand something 
completely?
	Please, any recommendation of how I can eliminate this "jack zombified" thing 
and understand the whole realtime issue is welcome.

Thank you in advance.