Well, could be. Especially in the car. But, setting you mention didn't help me.
And for the record, Airplay doesn't stop - it keeps thinking it's connected and streaming as if nothing happened. Packets just don't seem to reach the Airplay enabled device. It's as if suddenly (after a reconnect of VPN or something) iPhone suddenly begins sending packets beloning to the local network via the VPN tunnel even if it should not.