Thanks guys,

Manning, yes I was connecting the audio out into mixer I also tried using the usb throught a usb interface (uca222) into mixer and it didnt help. I tried lifting various ground to no avail only thing i couldnt do was use 2 balanced 1/4 (t,r,s) from the guitar rig controller into mixer , I'm using regular guitar cables.
Also I was getting some pops from the guitar rig and they are now gone so I guess for now i'll use 1 laptop for that dedicated purpose.