Correct, Audio mutipads do not loop... unless you design them in the audiostyle app (Audio Phraser)
https://europe.yamaha.com/en/support/updates/yap_win.htmlBut if you do that, I dont' think it will change keys, as Audio Phraser is designed for an audio loop of a drum pattern.
Not knowing what you want to do, I have to ask: could you not simply set the arpeggiator to say Right 1, let's say you want a megavoice guitar strum, so you could set right1 to a megavoice guitar, split Right 3 so that it's above RIght 1 and Right 2, and then play whatever you want on RIght 3 for the melody, while changing strumming chords by your chords on Right 1 (and make sure the select the arpeggiator to Right 1 only in this case)
Mind you, you could also just turn ACMP on, any of the fingered (ie not full keyboard) modes, and turn on an existing guitar strum multipad (or really, any other) and change chords in the ACMP area and the chordal multipads will follow your chord changes (not the percussion ones). Then you'd be free to use Right1, Right2, Right 3 for the right hand melody.
Again, not knowing your intention I can only suggest solutions based on my guesses? Are you trying to create a custom strum?
Mark