Vento - I feel it

I have purchased my car few months before. I have made lot of search on internet, took lots of test drives, online comparisons, customer reviews and practical feedback from true users. As I was looking for economical comfortable sedan for my parents, I have looked for comfort, easy effortless driving, safety, intact built in quality, good painless service most important is fuel efficient both in city as well as highway, so that they should not think about taking it out anywhere. After a quantum of survey, I have decided to go for Vento comfortline diesel and after these many days I feel like I made a bingoooo.. My parents found it all they need there is no complained from them as of now; good fuel economy, Easy comfortable driving, better control, obviously German brand well built in quality (as explained by company executive, galvanised body even with joints and all) Spacious good safety features With all that I am pretty happy with my decision. But with all that good, I am finding that the engine sound is increasing as the days are passing. I got it checked on service centre but nothing improved much I don't know why. But with this many good and some pranks, I will refer my choice to other and once again thanks to Volkswagen for providing all good to us.