I've bought an ibanez rg321ex guitar recently. it has INF1 for neck pickup and INF2 for bridge pickup.

the problem is, when i selected the bridge pickup, turn the volume and tone all the way up, there were high pick humming coming out off the guitar.

so, can anyone tell me how to fix this problem?
i've checked them.. and its seems fine. there is no loose wire. actually the it's not humming. more like high pitch squealing. and its really pissing me off.