Though probably we'll just end up screwing an Android tablet to a wall behind the bar and running an audio cable from it's output jack to the amp. (Often the simple oldschool way of doing something is the most appropriate and least troublesome. But I've got to entertain my desire to over-complicate everything by working out how to put a server into the middle of it.)
Discussion
nostr:npub13ruqn3wt7y3kwssdfdwfgt9fuy8p4ge4tf3quxg8hwvnlyjc57wq0t67kn At the Haymakers and Dev we just have an audio cable from the general-purpose computer behind the bar. At the Queen Edith it's an Android tablet screwed to the wall because there isn't enough space for a computer.