By coincidence, I have someone with a URC aurora remote, and someone with an MX900, both having similar problems.

Aurora: Had a command to raise and lower a TV inside a motorized cabinet. Suddenly it stopped working. The commands on the remote were "raise" and "lower". It beeps when those buttons are pressed. Is there possibly a setting on the remote button interface that has somehow been toggled and disables the feature from working? I think it must be using RF but I am not 100% sure.

Another client has an MX 900 and it works fine except that it's suddenly stopped. All the controls work fine, except that the volume no longer controls the Denon AVR. When pressing different activities, the remote will change the Denon input by RF, I am certain of this. But the volume buttons stopped. Is there possibly merely a button press that needs to be toggled on the remote for the volume to work again?

I'm also going to look into the specifics of the cabinet and the AVR, but wanted to cover all angles before delving into MX Editor to try and fix these problems.