New to the forum and posting a thread for the first time so sorry in advance if I am doing something wrong. I have a Reborn 2007 (prosmatic) and I am having some problem with the brakes. When I press the brake, especially at slow speed, there is a cracking sound that comes from the back tyres. I tried to test it whether it is particularly with the back tyres or all of them by pulling up the hand break slowly and it is for sure from the back tyres (because hand brake is attached to back tyres only).

It used to be less but now it is becoming more and more. Any suggestions as what could be the problem. Has anyone else experienced something like this?