Today I was driving along when suddenly there was a moderately loud metallic chafing noise from the front of the car. It changed in pitch as the speed of the car changed. I deliberately braked hard to use the disc brakes and it made no difference as the noise restarted when I sped up. There was nothing stuck underneath the car, as far as I could see. When I stopped, switched the car off (into Park) and on again the noise disappeared and did not recur during the journey, nor in the next journey. Any suggestions ? 2019 94 Ah REX.