Apple TV3 to Airplay on AE

I have a setup for my backyard patio which includes a new Apple TV. I want to be able to send the audio to an Airport Express through Airplay which is hard wired into my reciever in the house. When I select the Airport Express it connects but the audio can barely be heard through my airport Express speakers. What am I missing? I have checked all the volume settings and they are at Max but not coming through as it should. Anyone have any ideas?

Thanks

Jerry