I've been using RDS since the inception of the system and I've never had such a button.

But now I know they exist, I can see that it would be invaluable and can't imagine how I've done without all these years! Especially as we have been told that the upgrade on the Empeg tuner is a way away.

Maybe it would possible to write it in to hijack as a button re-definition - but I would hate to lose the the source selector on the volume control.