I have no idea wad wrong with my car. Rough sounding and vibrate happens when use for high speed driving. I have only 1000 kms on my car. The car is totally new and everything run fine except the brake system, and I have no warrantee ( I bought it from gray market in Thailand and it's cost me about 87000 US dollars here in Bangkok very expensive though) and the car has squealing brakes problem. Anyone pls help me how to stop these

 

moreover, high frequency vibrations when braking in high speed driving as i can feel by the car and brake padel not the steering wheel

 

That sounds like warped brake discs / rotors.

What happens is the disc gets very slightly out of shape and so when the calipers grip it, the calipers are fixed firmly in place, so it's the warped disc that has to move back and forth. Since that's fixed to the wheel, it causes vibrations.

The cure is new discs and more care warming and cooling brakes - don't brake hard on cold brakes and definitely don't let the car stand after you've been using the brakes hard for a long time.