One way to beat the sequence pauses.  It turns out once the sequence 'hangs' the timer loop in SequenceExecutor.cs was still running.  However, the TimingSource.Position was 0 in the test in _IsEndOfSequence.  This change treats a position of 0 there as an additional end condition. In addition, I added a Sleep(100) in _Play to make sure we don't hit the 0 at startup.