@llero The issue may be related to performing a read() and the output queue being empty. I was just wondering what version of the NCSDK you are using? Please try using the latest NCSDK version (2.05) if you aren't already doing so. Some fifo issues were fixed with version 2.05 that were a problem with 2.04.
You can also try increasing the size of the fifos. The number of fifo elements can be set using Graph.allocate_with_fifos() or Fifo.allocate() and changing the number of elements for each fifo. This will allow you to be able to have larger fifo queues.
