I find that I am getting dropouts. Not like I would with driver or latency issues.
Sometimes I hit a key or drum pad, my samples gradually come in after 3 or four hits. The first notes are most often inaudible. Sometimes in a quieter piece of music, the output becomes silent. My cubase outputs appear fine. I can overcome the problem by turning my cubase output up over 0dBfs but then after the kick start, it is too loud.
   I notice it more with sample based instruments more than processor based instruments. It works well but far from perfect.
   It seems to me as if there is a form of resistance but my interface is optical.
Do the ADAT leds get dirty or weak? Would optical cable cause it?