Apple TV Music & Menus Problems

I've been using my Apple TV for a year to stream music from from iTunes account (through Match, I believe).

Since the recent major Apple TV update that brought the user interface in line with other Apple OS changes, I can't get my music to load. iTunes Match is on, my ID is signed in, but when I go to Music > My Music the screen says "Setting up your Apple TV to stream music from iTunes Match..." It begins to load/update, then never stops working.

To make matters worse, a lot of advice I've seen in these Apple Support message boards suggests that signing out of my Apple ID and/or turning off iTunes Match, then signing back in and turning Match back on should work. Well, both the option to select my ID and to change the on/off toggle on iTunes Match are no greyed out in the menu screen.

Does anyone know what's going on with this? Why won't the music streaming finish loading? And why are these menu items greyed out? Suggestions?