Any question answered...

Nitto Riser Creaking

So i recently put on some nitto risers with a nitto jag stem. At first there was no noise however it is now very prominent. Im pretty sure its not the stem as when i use my drops there is no noise.. Just when i pull on the risers (i.e. going up hill) i get the creak.

Any ideas why?

They're a fucked pair?

http://www.euroasiaimports.com/productcart/pc/RECALL-INFORMATION-d3.htm