Re-triggering event structures after queue purged

I have a vi built with an event structure that allows the user to stop the tests.  I am using the flush queue subvi in the producer loop to remove the remaining elements.  Then the user may fix the problem and again press start, starting the tests all over. 
About 50% of the time, the event structure will not restart, and the vi will need to be stopped and re-started. 
There must be something I am missing that is not allowing the event structure to re-start. 
Is the position of the flush queue correct in my snippet?  
What could cause the event structure to not respond and how can I troubleshoot it?
Thanks.
metzler CLAD
Attachments:
producer snippet.png ‏56 KB

You should take more care about your error handling. Propably you just miss the errors that cause this behavior.
* At the while loop, use shift-registers for the error wire.
* I also recommend you to place a case around the event structure that catches errors and stop the loop.
Felix
www.aescusoft.de
My latest community nugget on producer/consumer design
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