Thanks for the feedback, @chris_g1
The contents of the playlists doesn't seem to have any impact. Most of my playlists are filled with a mix of Apple Music files (subscription), local mp3, and some old purchased iTunes music. And, I've also tried playlists comprised exclusively of a particular file type and they exhibit the same weird behavior (Re: when clicking a playlist from the sidebar, the app plays a track from a different playlist, or sometimes it just doesn't change tracks at all).
I should note that the playlist's hierarchy also doesn't seem matter. In other words, whether it's in a folder/subfolder/etc or whether it's sitting in the root, it doesn't seem to matter. Same stupid behavior. On some rare VERY rare occasions when it actually works as it should, I've only ever seen this occur with subscribed Apple Music playlists that are sitting in the root (because you guys don't allow people to move them into folders for some odd reason) (e.g., Favorites Mix, New Music Daily, etc.). In any case, when that occurs, it just seems like dumb luck - i.e., it's incredibly rare. When double-clicked, they almost always play tracks from other playlists, too.
As for the Safe Mode behavior, it's difficult to test this particular problem in that setting, given its audio limitations, etc. However, it behaves the same way. When I double-click on a playlist from the sidebar, it attempts to play a track from the wrong playlist (i.e., it acts like it's trying to play the song shown in the display at the top - and this is easy to confirm using the shortcut ⌘L ("Go To Current Song"), which inevitably takes me to the track it's trying to play from a different playlist). I should mention, however, that there were also several times when double-clicking a new playlist from the sidebar that it would not even change tracks. Though this odd behavior seems specific to Safe Mode, which is obviously not intended for playing anything.
As for whether it occurs for all users on my Mac, I have no idea. I'm the only user of the mac, and I don't feel like creating a new user, with new music, etc. I'm sure it's specific to me. I'd find it hard to believe that it would do this on a fresh account with new playlists, etc.
Relatedly, I should mention that I have tons of playlists! Many of these have been around through numerous iTunes/Apple Music updates, etc. In addition, I use a lot of folders to help keep them organized. That said, Apple Music behaves the same way with brand new ones (as it does with the old ones). The folder/root thing also doesn't seem to matter.
And, finally, just to be clear, I can still play all of my playlists by navigating to them in the sidebar and then either (1) clicking the big blue Play button at the top of the playlist (at least when viewing them, as playlists - i.e., I'm referring to the blue play button at the top, next to shuffle button, above the description and below playlist title, etc.), and (2) directly clicking a track in the playlist. So, there's nothing wrong with tracks in these playlists. This problem is specific to trying to play playlists by double-clicking them from the sidebar, a behavior that's been around for about as long as I can remember.
What should I check next? Thanks for your help!
