Here's what I'd do:
Android tablet with USB Audio Player Pro and Fully Kiosk
Fully Kiosk can disable touch input and, using a motion sensor or the built-in front facing camera, can turn on the screen when someone walks up to the tablet/play button station and turn the screen off automatically once they leave.
It may even be able to start and stop playback automatically using the motion sensor. E.g. start playback on approach, stop playback on exit.
USB Audio Player Pro set to "Stop after song ends" so that Play must be pressed after every track to resume playback.
As playback device, use a DAC with 3.5mm Aux output with headset support (e.g. Meizu HiFi) with a custom CTIA to 2x RCA adapter that also has a button of your choosing wired to the Mic pin.
That way, customers can pause, play, and skip a track even with touch input disabled by Fully Kiosk.
You could even enable volume up/down control if you'd like.
For this, you can set a volume limiter in UAPP to avoid disturbing other customers.
You can also specify the volume step granularity to set how quickly volume can be adjusted.
A tablet screen would enhance the user experience by displaying album art, track info, track progress etc.
And the cherry on top:
Using UAPP's built-in 10-band PEQ you can apply room correction for cleaner playback.
A few "gotchas":
-Network connection likely required for Fully Kiosk to function
-For permanent installation, the tablet's internal battery should be disconnected to avoid pouch cell swelling from being charged 24/7.
If that's not possible, enable a charge limiter so that the battery is kept at 80% instead of 100.
-To have the tablet plugged into power and connected to a DAC, make sure it supports USB Power Delivery and use a USB hub with PD pass-through.
E.g.:
https://www.audiosciencereview.com/...8d-review-portable-dac-amp.21556/post-1045358