Trouble with home share audio using ATV2 and Yamaha RX-V475 AV receiver

When I home share play a movie the audio isn't available. To get the audio I must hold down the ATV2 remote and change the speaker setting to the AV receiver. This has the effect of putting the receiver into Airplay input mode and I loose the video. If I reselect the correct input (HDMI channel) on the receiver for the ATV2 connection I get the audio back with the video. Any ideas?