Why am i getting grinding noise on fender stratocaster?

i jus got this brand new strat, and as soon as i started playing i noticed that when i bent the high E string(the thinest ne) and then back down it makes a grinding noise,i traced the prolem and it seems to be a lil piece that goes on top the B and E strings,and when i bend it makes it grind and get this anooying sound when bending or even in vibrato,what can i do????please help