When in demo song mode ? What even is that , never heard of such mode
It's next to the volume knob on the hardware. Personally, I don't think that's a feature that deserves a permanent implementation on the control panel.
who actually really uses audition buttons ?
It latches and is actually helpful for freeing up a hand when editing parameters that can be accessed by the shift button. Just don't tickle the bug that's there by using the Transpose button at the same time!
See related thread: Shift Button Conundrum