Whistling Wheel :S Suggestions Welcome

Not sure if this is the right place to post this threat, apologies if I got it wrong.

My front driver side wheel has been whistling when at slow speeds (30 mph and less) on right hand bends (gentle bends). I had the wheel off to check all the pads etc to see if I could spot anything. The Skoda garage (when it was in for service) suggested that they think it could be the 'Front suspension role bar retainer bracket' as its split, although I am not convinced that is the cause.

Anyone had a similar problem or have any suggestions as to what it could be? This is on a Skoda Fabia vRS (2004)

Thanks