Date Keeps Randomly Changing In Windows 7?

I have a asus N61 about 7months old. running windows 7.

For the last few months the Date keeps randomly changing, usually the actual time is correct, but the date keeps changing at random intervals, sometimes it wont happen for a few weeks, then it might happen every couple days. then nothing again for a week or 2. and usually it goes forwards about 4 or 5 days. sometimes back a few days.

don't post anything about CMOS, As this is a new laptop, so it shouldn't be the cmos battery, ALSO it doesn't happen every time i turn the laptop off, so i doubt a old cmos battery would work sometimes and not others.