Why has my audio from Apple TV to Airport Express suddenly stopped working?

Hi.

For over a year, I have had my Apple TV and Airport Express connected together and the audio worked perfectly fine. All of a sudden the audio playback on movies and Netflix had dropped off considerably. I now have to turn my amp upto 70 to get even the slightest sound. Music plays fine to the AE but not Movie Audio.

Anyone else having the same issue??

I'm confused because it's worked ok for a year!!

Any help please??