Why is my Sr suntour making a wierd noise,help needed

Its a air fork and I have heard that the coil ones do that bat never about the air ones, I have max rebound and it stops clunking when I turn the rebound down but I like having high rebound so I’m wondering if there is a solution 

Sent mine to the mechanic for that. seems it needed to be dismounted, all cleaned up ( a lot of dirt inside) and oiled up again. hope it helps