Well first (correct me if I am wrong) but arent balanced Cables TRS (Tip Ring Sleve) cables? Or in other words Stereo cables. Your guitar cables wouldnt work for this reasons because all of the guitar cables I have seen are Mono. Another thing, on the Mq3 (just got one my self) from my understanding, is that you would only hook up the left output of the unit to the Soundcard. According to what my bro read in the manual, it says the reason they give you 2 outputs is so you can run one to your recorder and one to somthing else if you like. And actully we first started with both outputs running into our Delta-44 and having problems with noise with that.