CharacterController+ colliders= fast speed??

right, I have a character controller, and whenever I “rub” on box colliders, I sometimes get a large speed boost for no reason. is there any way to limit the maximum speed of a character controller? I’ve tried adding a rigidbody + several speed limiting scripts but to no avail. please help!

Can you upload the project, to check out the problem? I have no exact idea, why does it do that.