Question Why i get this strange sound?

[Bojaneee]

I just bought a new pc and found my HDD is making some occasional very unssetling CLUNK sound. It doesnt sound like its normal. It happens when the pc is in idle state as well. I can hear it on every 15 min - 30 min. Otherwise the pc runs very well overall, the fans are quite but that sound is very unpleasant and irritating. Any opinions what might be?

 

[Bojaneee]

Its a new pc from tech store, prebuilt configuration.