Moin, for some time now our escort from the left front wheel gives a high frequency tone of itself. Don’t come up permanently and can be compared with bird singing or a fieptone. Unfortunately, you only hear it during the ride when you drive past something reflective (e.g. wall). Have brake or wheel bearings suspected. However, wheel has no bearing play and does not make otherwise typical wheel bearing sounds like poltern etc. When I type the brake pedal briefly the sound sounds short-term off f, but could not test it with certainty yet, because the noise does not occur permanently as said. Brake is made before 10,000k except on wheel brake cylinders, the noise only occurred after the disc and covering change. The surface is still neatly on it, brake is also not fixed and rim does not get hot. Is this a brake-typical noise, e.g. when the coverings grind easily on the disc? Greetings