Just replace it with a paper substitute and re-regulate. They are a little thick and the adj. screw head is pointed and eventually digs into it. Thinner is better in this case, the type of material doesn't matter. Standard copy paper will work nicely .003" thick.
Check to make sure the hinge tube is not worn. I've seen a few over time that need a little swedging. That click can also come from the tube against the hinge tube. A consequence of Split E mechanisms over time.
If your regulation is stable and it is just the click then swap the silencer out. If it is a click and the regulation is funky, check the hinge tube fit.