Why is there noise coming from the front wheels of my Toyota Auris?

I own a 2016 Toyota Auris 1.6-litre diesel that's done 18,200 miles. The car was purchased brand new in February and it had its first service in July. Since around September I have noticed a high pitched noise coming from one of the front wheels of which I cannot identify. It is totally random and a tap of the brake pedal stops it and if it starts again a harder stamp on the brakes stops it altogether but it comes back randomly. The service manager at the dealership reckons that there is dirt in the brakes and removing the wheels to check this isn't covered by warranty so I rejected this because I think that he's wrong and I've just kept on driving. I have noticed that the steering is becoming slightly more vague. I'm thinking of going to a different Toyota dealer about this because I don't like these issues with the car. Last year I owned a brand new Toyota Yaris hybrid and at 22, 000 miles there was similar issues with the steering but no ringing noise from the wheels. Again this service manager arranged arranged for a technician to take it for a test drive and also a salesman had a drive in it and they said that the car was normal. I had enough and traded the Yaris in for my current car. A few weeks later I received a letter from Driving Standards Agency informing me that the Yaris was being recalled due to an issue with the engine mounts which could potentially affect the handling of the car. I was furious about this and contacted them to let them know that I no longer owned the car and it is at the dealership for sale and it took quite a while before they got a buyer. What do you think that I should do? I have absolutely lost confidence in the car.
By 18,200 miles the front tyres are going to be wearing and that would explain increasing vagueness in the steering. Might help to reduce the front tyre pressures very slightly. The 'ringing' noise might be a slightly loose backplate to one of the front brake disc caliper assemblies.
Answered by Honest John on

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