Please forgive me, I've been reading and researching for a couple days now and every time I think I found the solution, it doesn't work. I switched from an analog connection to a S/PDIF on my Scarlett 18i20 to free up the two guitar inputs. I have the out from Kemper going in to the 18i20 S/PDIF. The interface is connected via USB. My Focusrite controller is set to S/PDIF 1-2 with internal clock source. I tried using S-PDIF source but lose my output sound from my iMac. The Sample rate for all devices is 48 kHz set. BUT, I hear an occasional "tsk", it's faint but I hear it. It's like a cricket that is in the room that you can't find but know it's there. Please, can you help me rid this cricket? Thank you so much!