here is the head unit...
and the "magic box"...
Could you give some more details in regards to this "magic box".
Yea It looks like you should be able to plug the rca cables from that box into the input of the sound card, you would need a RCA -> 3.5mm(headphone jack) adapter. Or you could leave the audio output not plugged in and not have the dinger.
The only issue to that would be if you had an onboard sound card that only has 3 jacks and you have it set to 5.1 mode, then it usually switches the input to the rear speaker output. But if you got a soundcard then you would definitely be able to do it.
Also the sound wouldn't only come out of the speaker when the computer is on.
Another option would be to put the output from that box directly into your amps, using a RCA Y cable with two inputs and one output. That way the sound would come out whether or not the computer was on.
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