Ive had this problem for a while. Seems to be dominantly after putting head into my brakes. I will come to a stop and as I brake near 10mph there is a slight brake squeal in the front left corner. This would be ok. Except it happens around 5mph when im not braking as well. I can hear it squeak in one specific spot each time the wheel revolves. Just replaced all my rotors and pads and the sound came back. No stuck pistons. Pads were evenly worn. New pads were lubricated thoroughly.