Ok, earlier this year replaced AC comp, Evaporator and orifice tube. Had it vacuum tested/recharged by a licensed mechanic. Worked good until a few days ago. Compressor seems to have been growling a bit just before AC stopped blowing cold air. Jumped the low pressure switch and it clicked on the clutch over and over rapidly. Seems I have may have a leak somewhere. I dont see any obvious leakage. Any other suggestions on what else I can check.