Menonrajesh
Similar thing happened to me in 2000 when I bought a brand new car from showroom while comming back to home I heard similar noise comming out from tyres and I was fortunate inuf to find what was wrong with it,now guess what I did

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All 4 tyres were loose and not fited fully with drum-- can You belive this?I was so shocked to see such things and this could have ended in disaster,then I called the dealer from my cellphone and got a reply that it is strange as such things never reported to them(this perhaps happened may be due to someone asked for tyre change and insist for some fix tyres brand so showroom guys perhaps removed them from my car to his car,the only reason I could smell,just guessing).
In short just check all 4 wheels of your car and post your feedback if this is the case with you.