I replaced a 2 year old HTIB that started making a "feedback" noise whenever I watched an analog source using the digital optical audio. I bought a new Samsung HT=WZ412 and now that problem is solved, but there is a new audio problem. Now when I change channels, there is a weird ZAPPING noise that sounds like a Tazer. I went to the store and replaced the receiver and the problem remains. This is the setup: Tivo HD hooked up to an OTA antenna and output the video to my Panasonic 42" plasma monitor via HDMI (there is no audio on the display because it is just a monitor). For audio I have the digital optical audio output on the Tivo HD hooked up to Samsung HTIB. This is what it looks and sounds like: http://www.vimeo.com/2549121 Does anyone have any idea what the problem is or is this receiver just incompatible with the Tivi HD.