Hi, Tim This problem normally occured when your VI constantly switch back and forth to the user interface thread. Probably you have some VIs, functions or operations, which running in the UI thread: - Property Nodes - Menu Control VIs - VI Server - Thread Unsafe CINs or DLLs. Be sure, that all of elements above not used in your deterministic VI, and all DLLs calls are reenterant. Hope it help.
