Yeah, it's weird. The address on the bottom is correct. I changed it to a different address just to try something, but no change in operation.

I don't understand what's going on.

Yes, I understand the output of the remote is either RF and/or IR.

The old remotes are still working, you just have to push really hard on the keys. They were programmed with the old MX-900 editor. The new remotes require the new software as I'm sure you're aware.

I'll play around with it some more to see if I can see a mistake somewhere. Like you say, it's pretty simple.

I'll write a really simple one device program and see if that works. Thanks for the input.