Accessing microphone on iOS mutes audio

The release notes for AIR 15.0.0.27 state that one of the fixed issues is

[iOS8] Requesting microphone access terminates all further audio.

However, I'm still experiencing this with 15.0.0.356. If a user runs Spotify or another audio app in the background while playing my game, the audio is fine until I access the microphone, after which audio gets muted.

If this is expected behavior in iOS and audio can't play while the microphone is active, what do I do to restore audio again?