There are a number of threads on this subject. I believe low speed brake squeal is caused by brake dust embedded in the pads. This can be cured temporarily by braking hard from speed 2 or 3 times.
I didn't have this problem with the original Textar pads but I have had the problem since I fitted new discs, pads and sensors with Pagid equivalents. The Textar pads were quiet but filthed the wheels very quickly. The Pagid pads squeal but are kinder to the wheels.
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