I am not a very good electrician. I do, however, have a lot of experience running wires for various stereo components. Which is why this particular problem really irks me that I can't come up with a better solution.
Here's the deal. I have a HD digital cable box and a Tivo. I love Tivo because I can record shows and keep them forever on my computer, something the cable companies will never allow you to do. My point is to establish why I don't just get the cable company's HD DVR box.
The problem is with audio. I run audio from the cable box to the TV and I can watch HDTV with sound, but I can't record any digital cable channels on the Tivo. So I run the audio cables from the cable box to the Tivo. Great, now I am watching HDTV in silence. I wish like all hell that the second pair of audio out connectors on the cable box actually worked, but alas they do not.
My solution is rather backwards. I ran audio cables from each of the sources on the TV (Tivo and cable box) to a 4 way AV splitter and then ran the OUT to the Tivo box with the cable's audio running into the Tivo. In this case, the Tivo basically functions as a passthrough for the cable box's audio and the splitter lets me listen to either source while viewing it.
I still don't get exactly why it works though. If the in's and out's on the splitter are labelled correctly then I shouldn't get any sound on either input, but I think they're "in" and "out" can be reversed as I did it.
Am I missing something? Is there a better way?
Corrected Crossing Wires
So it sounded good, right?
"My solution is rather backwards. I ran audio cables from each of the sources on the TV (Tivo and cable box) to a 4 way AV splitter and then ran the OUT to the Tivo box with the cable's audio running into the Tivo. In this case, the Tivo basically functions as a passthrough for the cable box's audio and the splitter lets me listen to either source while viewing it."
Yah, not so much. It turns out that the Tivo is not a good pass through and it also delays the signal slightly as it caches it.
So here's the real solution and this makes even less sense than what I came up with before, but again it works :
from out cable box to out 4 way switch
from tivo out to tv s-video 1 in (the only one that is somewhat straightforward)
from tivo in to switch #2 in
from switch #3 in to tv component #1 in
did ya follow all that? good, cuz I have no frigging idea why that works, so maybe you can explain it to me.
I also figured out how to run both at the same time by pushing in both of the buttons at the same time, effectively creating a powered split instead of a switch.