This Bluetooth speaker might be just the thing you need. The wireless communication uses Bluetooth to ensure a fast pairing.
BuyKingston
Manhattan Bluetooth Shower Speaker (Clearance Pricing), Waterproof design with suction-cup mount, Omnidirectional Mic, Integrated Controls, 5 hour Playback time, Range 10m, Output 3W, USB-A charging cable included, Bluetooth v4.0, White, 3 Years Warranty,