Why does the brake make noise when not pressed but not when pressed?

[StJessica]

The reasons why the brake makes noise when not pressed but not when pressed are as follows: 1. New pads installed on old rotors—old rotors usually have grooves, and the new pads may contact the upper and lower edges of the old rotor, causing noise. Solution: Chamfer the edges of the brake pads or resurface the rotor to resolve the issue. 2. New pads installed on new rotors—if the new rotor or new pad has excessive unevenness, poor bedding-in between the rotor and pad, or uneven wear on one side, it may cause noise. Solution: After using the brakes for some time, the rotor and pad will bed in properly. If the unevenness is severe, reinstallation may be required. 3. Poor retraction of the brake caliper, causing drag and premature volatilization of the organic material in the brake pads, leading to noise after some use. Solution: Inspect and maintain the caliper, check if the brake pads are intact, and replace them if they are burnt.