Or given lots of hotels are likely setup the same, write an app that lets people take advantage of this / broadcast their own tunes to these services, so they c

Or given lots of hotels are likely setup the same, write an app that lets people take advantage of this / broadcast their own tunes to these services, so they can choose their own lift music in a Sonos-like way. If this were an officially endorsed thing, hotels could even stick a Physical Web Beacon (https://g.co/beacons https://g.co/beacons) in the lift, pointing customers to your app. All that said, I guess my above scenario, headphones may be a simpler option ;).