I do not see how I can hook up 2 sets of RCA cables for each line.You don't use 2 sets. Assuming that your AutoPC has an auxilliary line input, then just choose
one pair of outputs from the Empeg (either the fronts or the rears), and put those into the AutoPC's line input.
If the AutoPC doesn't have a line input, but it does have a line output, then you can go from the AutoPC's line out to the Empeg's line in, using a similar scheme. But for that, you need an amplifier. You didn't say whether your AutoPC is already playing through an amplifier or whether it's using built-in amplification (I don't know if the AutoPC even comes with its own power or not).
The relative merits of "which one comes first" in the audio chain are discussed
here.___________
Tony Fabris