I have Line 6 Toneport Ux1 right now my speakers is connected to analong to line 6 by 1/4 inch. and the other side of speaker is connected to computer and my mic is connect and work and i can record but i wanna connect my mixer as well i was wondering if you please help and the other thing is when i connect my headphone to line 6(using 1//4 inch) i can hear the vocal voice and the beat but i just want the beat is it possible or i should use 2pcs. i just want to record voice and im using sony acid 7.0

thank you