Yamaha MusicCast TSR-400 User Manual page 294

TROUBLESHOOTING > When any problem appears
The iPhone does not recognize the unit when using AirPlay
(
The unit is connected to a multiple SSID router.
Access to the unit might be restricted by the network separation function on the router. Connect the
iPhone to the SSID which can access the unit. (Connect it to the Primary SSID at the top of the list.)
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