As someone who's never content with just the 'standard features' that a product has to offer, I've been playing with some of the HME apps that are around for Tivo. One that I've found particularly good, and worked right away was Audiofaucet which streams (yes streams, not transfers) audio from your itunes (or other music) library to your Tivo, and consequently any connected audio equipment. Playlists and cover art are supported which is nice. Make sure you change the Audio Output option (under settings in the Tivo app) to 'Stream to Tivo' or the music will come out of your PC speakers.
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