I've just started having a similar problem since I updated to 11.5.1
I think it is has something to do with Apple Music not registering as a media source. The little media icon that appears in the menu bar does not show for the Apple Music app, but does for other media such as you tube in a browser and Spotify. I looked around in the preferences and there is nothing there. Very clueless about how to fix on my end :/
Harry286
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