Bubble sound from my MacBook Pro

Hi, I used my new Macbook Pro for 2 months. And I think I just heard "bubble" sound (something like 'pop' sound) frequently 3 weeks ago. I'm not sure where it's from. It seems like it comes from the harddrive . Has anyone facing this weird problem also? Is there any solution or suggestion? I'm worried that it might be a problem with my hardware.
Thanks!

*Moved thread to appropriate forum - Question is not a FAQ Submission -> Hardware/Apple Notebook*

It does sound like a hard drive problem. Have you been having any trouble installing new apps or gotten any error messages about hard drive troubles? If so then you should probably want to get that checked out. But, if its making the sound and you aren't having any problems then I would just use it until something worse happens. Then again you could always get it checked out just in case.