front brake

hello guyz, brand new 2017 fz09 here, with 400km on it. the sound started about 50km ago, when driving at slow speed( about 20km/h) theres is a sound that come from the front brake(I guess) while the wheel is rotating, either in gear or in neutral, you know that kind of high pitch annoying kind...

Have what I believe to be a defective front brake master cylinder. This was originally on bike # 2. Problem is that it acts like it's sucking air, or something. The lever will randomly get soft in traffic and even start to drop to handlebar very close. A quick pump brings it back to a...