I've had a similar problem for a long time but intermittently on RS232 Port #1 only. I would like to have more information about your setup.

1. What RS232 ports are in use?
2. On each RS232 port, do you use ProntoScript or standard one-way actions to control the equipment.
3. Are there cases where the equipment being controlled fires lots of responses that might get ignored which could cause the buffer to fill up (1024 bytes).

The only way to resolve the problem for me is to power cycle the RFX9600 and when I do, voila, Serial Port #1 works again. FYI, I use one-way actions from PEPv1 and the equipment is a Denon 5805 receiver.

Lyndel