I understand your dilemma. After searching all over the place, I still have no answer. I think the sub may be the red connector. Will it do damage if you get it wrong? I doubt it. The sub will get the frequencies intended for the center, and the center will get the frequencies intended for the...

I'm a bit tired, so don't take my word for it, but I think it should look something like this. That should give you an idea anyways.

Actually it looks like the Centre and sub channels require a Y cable too. Sorry.

Make sure it is two RCA's to one 3.5mm though. Not  two 3.5mm's to one RCA.

Yes, RCA to 3.5mm Y cable sounds right. The one that came with the card is female 3.5mm I think. 3.5mm jacks combine left and right channels into one connector. With RCA connectors, as seen on the Xonar H6, there is a separate cable for left and right. The Y cable should allow you to combine the...

Not with the Essence ST unfortunately cladisch. I don't know what comes with the H6 expansion board, but I'm guessing that didn't include the aforementioned cables either.

Hello, I think I might be able to help. The bad news is that the solution will cost you a little. On the actual soundcard, there should be two phono outputs (I think thats what they are called). They will be red and white I think. Those are for the front left and right. You will need a cable...