Controlling an Apple TV without a TV screen

Perhaps I'm not phrasing my question correctly but I have been unable to find a solution. I have an ATV 4K 3rd gen. device. It's connected to my TV via HDMI and I extract the audio from HDMI and play through my home hi-fi system via a D/A convertor. All good while watching TV. However, I would also like to play from Apple Music via the same sound system and this works fine so long as I have the TV turned on and can visually navigate Apple Music. As everything is currently connected, if I turn off the TV, I can still hear the music but I can no longer see what I'm doing. OK for listening to an album but not so good if I want to dip in and out of artists.

Is there any means to see what I'm doing without turning on the telly? Obviously, I've Music on my iPhone but I can't think of a way to use this to control the ATV. It doesn't mirror what Music is doing on ATV.

If anyone knows any way around this, I'd love to know. Thanks in advance.