This seems to be an issue with TiVo HD and certain TV's/Amps.
While changing to PCM fixes it for most, you lose the 5.1 channel encoding that Dolby Digital offers on some material.
I'm not aware of any other fix, and unsure if TiVo are looking into the compatibility issues. It's not just Australian units that are effected. The 2nd batch of US TiVo's are have the same problem with certain TV's & Amps.
Peter.
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