Popping/creek from passenger leaf spring

Hey guys I have a pop or creek when I go over bumps or get on the gas. I went under my truck and compressed the leaf by hand in front of the axle and it made the popping noise. How do I fix this?
I have a 2011 trd sport short bed and I have a two inch block.
I plan to replace the block with an add a leaf but I don't know if that would be in vain.

 

Since you have the 2" blocks check the tightness of Ubolts. It may not be your problem but I'm about 95% sure they need it.. If that doesn't do it , just bite the bullet & lower axle , check out springs..