Apple Musics protocol is Airplay, not Chromecast, which is supported my the original WiiM Amp (not the recently launched pro), so this is the correct way to stream it to the Amp. Through Airplay, Apple Music sounds.. not bad, but considerably better than Spotify. Both services are vastly inferior to high res ones like Qbuz or Tidal which offer much better sounding formats like FLAC with increased sound quality.