Thanks for the response GuerillaBuild. I am controlling a TV via RS232 for PWR on and off; and a Denon AV processor which does a PWR on, and INPUT on start up and VOLUME UP/DWN. When the IR locks the RS232 does still work. If it is a buffer overrun, sounds like a firmware issue that I would expect more people to experience.

Does anyone know of a way to issue a command (pronto script?) to flush the buffer to test this theory?

Thanks again to all...
Jerry