Earlier I posted this message under the MX-500 forum, but no one has yet responded. Perhaps there is someone in this forum who might know:

I just picked up the URC4640 4-device remote with the intent to program my MX-500 with discrete codes for my Yamaha receiver, my JVC switcher and Audiotron mp3 player in addition to my VCR's, DVD player and TV.

Since there exists no 'AMP' or 'AUX' button on this OFA, am I out of luck in using this remote to program in advanced/discrete codes for those devices into the MX-500?

Reason I ask is that whenever attempting to enter a device code for my AUX and AMP devices (per the hifi-remote website), the OFA appears to reject those codes as invalid. I only have VCR, DVD, TV and CBL/SAT as device choices on the OFA, so I choose one of them hoping that the OFA will accept the code for an AUX or AMP device...

Thanks in advance for any insight anyone might give.