I recently swapped out my dvr to put in the 811. i have an extra tivo but i'm unable to use on to record standard def b/c the audio is coming through digital input, which tivo doesn't support. is there a way to set it up to get the signal using s-video for tivo and component for the 811? also, i have an extra line coming from the satellite - can i use that line to add a 508 receiver and then somehow toggle back and forth between the 811 and the 508? thx