Here are some other ideas from the past

My suggestion would be to push the volume button to pause the player, thus freeing up the top button so that it could always move you up one layer in the playlist hierarchy. I think this would make navigating the playlists (and other features) more consistent and logical, and would get rid of the annoyance of always having to return clear to the root of the playlist tree after starting a playlist.

tanstaafl.

"There Ain't No Such Thing As A Free Lunch"