iTunes 12.4/12.4.1 Empty Black Window when listening to Radio

I use iTunes Radio to listen to ESPN Radio throughout the day. Starting with 12.4, and persisting in 12.4.1, starting a radio stream causes a large empty black window to open. It looks like something that would be used for watching a video stream, but this is audio-only. Is this a bug, or is there a way to disable that window? If I close that window, the audio stream stops. I've been minimizing it, but that seems kludgy.....