I am trying to get AC3 audio from 125W. I am using a Viewsat PVR 7000, going from its optical audio output to an RCA 5.1 Dolby surround sound system. When on a non AC3 station the audio comes through clear, however when I tune in an AC3 station, the only audio I get is a continuous clicking sound. The Viewsat is set to Dolby Digital = On. There must be something that I am missing. Any help is appreciated.