I would just like to give my problem and solution to this issue as well.
I had a 2 different sets of brake squeals. One was what most on this thread say happens. From a stop or just after applying brakes at low speeds I would accelerate and hear high pitch squealing up to 25mph. The other squeal being deeper in tone and coming from the front and when braking from 25mph down to 0 but only after a 35-45min drive.
I tried everything from getting the dealer to replace rotors and pads (still OEM Jurid semi-metallic) to then seeing this thread and then sanding any rust off the dust shields. Also, tried setting the parking brake to where it needed to be raised higher to engage. Then finally switched brake pads and it solved the high pitch squeal that most of you have.
So for the high pitch squeal the OEM brake pads were the issue. I switched to ceramics, also organics work as well.
For the low pitch squeal I tried sanding down my rotors with 120 grit sandpaper. I used a lot of brake cleaner on the rotors as I was doing this. It fixed the issue after I rebedded the pads in. Apparently at some point in time after I got a regular pad change at the dealer, they decided to test drive the car (possibly for another issue) and ended up burning in the pads into the rotor from braking hard down to a stop on the new pads.
Again, for low pitch squeal I sanded the rotors with 120 grit sandpaper and brake cleaner and rebedded the brake pads in. Also, check
this thread out and read the 13th post down for a better method of doing this.
Hopefully this helps someone else having similar problems plague them as after a year and a half of squeals I am finally free of them thank Jesus.