Hello, Since the interprocess communication between the different processes and the clock driver is somewhat challenging I would like to propose that we start thinking about a unit test in which we allocate 2 processes, each with a clock driver, which then at random trigger the emitting and the following. If each process then prints out the time and the current state of tempo and bpm we can see whether these two actually correlate properly. I'm currently thinking about something like this. When I will have toime to implement such a tester is not yey clear :-) Werner,-