Question Is this a normal sound coming out of my computer?

[ignasm265]

Take a listen ( zippy share, just press play button ) I'm assuming the sound is coming from HDD even though my windows are installed on SSD and HDD isn't in use while it's making that sound. It starts when i start the computer and stops after 15 minutes or so. Should I be worried about this sound?

 

[karenjoly]

Is this a joke ? April already ?