I have this same problem with my LT. I have tested this with different cables, pedals, and power supplys, and for the life of me cannot get rid of the noisy feedback from the fx loop. I am using one of the loops for the "4-cable method" and have no issues of noise being introduced from that. I am trying to add my whammy ricochet into my rig as the pitch wham effect leaves a lot to be desired.