1997 Integra weird sound from brake or??

Hi, i need help!!!!!!!!! my integra has been acting weird lately,I've got noise that started 2 weeks ago when i step on the brake. It is a metal squeal or grinding like sound but it doesn't do it all the time - it comes and goes. It does NOT sound like a worn down brake pad - but it does sound like something is scraping the rotor. Speed is irrelevant - it will come and go at any speed. Turning the wheel either way does NOT affect it. The sound will change slightly if I apply the brakes - but I feel NOTHING through the brake pedal.
Anyone know what the problem is???? Recently i had resurfaced both front rotors, and my mechanic says the brake is ok...... thanks!