Thanks for responding! As I said, if I test the TRIGGER commands from the IR Navigator, it works as expected. I'm wondering if this has something to do with me setting the MRF-350 to have discrete IR ports.

Port 1: TV
Port 2: AVR
Port 3: Cable
Port 4: Shield

I don't have the same commands blasting to all devices. With the MSC-400, you could modify a command in a macro to hit a certain port on the MSC-400. I'm checking to see if this is a possibility with the MRF-350.