As I understood, ATF in a normal automatic gearbox used as a medium to transfer the power. But in CVT, ATF is used as a lubricant where the power transfer happens through the CVT belt. We need to change ATF in a normal automatic box in 40K, I guess with CVT box we should be able to do more. Few years back I heard the same as what "Clark's son" mentioned. However we don't need to take any risk just to save Rs.13k though
I am doing my regular services from TL. They didn't suggest me to do a ATF change so far even though car is 2+ years old now.
But I got it done from some other place even at 15K on the clock as now car is 2years old and just to see whether noise goes off with that.
Back to the original topic,
I found another car manufactured in 2012/12 (same model) which has the same noise. So it looks like a common issue which I should not worry too much.
Thanks a lot for all the responses.