Just replaced front and back brakes - new pads & rotors. I have an awful high pitchy squeal/whistle when I am driving which goes away when I brake. Could it be a caliper? wheel bearing? Help! Its driving me nuts!

 

Can you determine the area the squeal is originating? Left front, right front ?
Once you isolate which side , start a very detailed check of everything you did.
Also , if the caliper is not free to move due to corroded pins , it might be hoilding the pad against the rotor.
Did you also clean with a rag the surfaces that the stainless clips adhere to so the pads are free to move?
Did you replace the stainless clips , they should have come with the pads.