I found out the problem to mine,inside the pads there is a safety strip
that creates noise so you get scared and rush to the mechanic. mine were so
worn it was it even caused a seized caliper. perhaps this is what your
problem could be
First take the caliper off, the noise should go away, it could just be the
brake pads rubbing on the rotor but inspect the pads and make sure they're
not worn.