Sounds tricky, but in the spirit of ideas...I have come across something similar where I have an internal clock controlling Case statements, all is fine unless one of my functions is delayed, then my clock is also delayed. I found it was an error in my byte size parameter which was producing a very large buffer, which was slowing down the whole VI. My suggestion for finding the delay/timeout woe is too monitor your block diagram [Highlight Executin mode]to see if you can detect another process delay that then affects your clocking. Although you say your counter still continues normally, perhaps some of the pulses are getting dumped. Good Luck - Doug
