Annoying popping doing dumbbell wrist curls

I'm doing wrist curls super setted with reverse wrist curls for 5x20 3 days/week. I just want big juicy forearms, a department in which I am really lacking.

I've worked up to the 10kg dumbbells and now my right wrist has an annoying pop (like something slides over something else, I can actually see it and it comes with a sudden movement when the pop comes). Anyone know of some technique change that could make this go away? Perhaps a change of dumbbell wrist curls to barbell or Z-curl bar?

I've tried angling the way I do the curls in different ways to no avail.

Thank you for your help.