This weekend just hooked up Samsung HLN567WDLP with Zenith HD520 Sat rcvr and Directv. Couldn't get Tivo to work and this morning they are telling me the HD520 isn't compatible. The HD520 automatically changes format either 1080i for an HD channel or 480I for the the rest. Evidently Tivo can't change the channels using the blaster, it doesn't work with the Zenith. Saw something somewhere, where someone said hook up a different connection etc. Is anyone else having this problem. Hopefully someone knows how to get around this problem. I am really bummed. Thanks. This is a great site and my first post.