Speakers crack periodically instead of playing the sound

Hi, my Blade 15 is now about 6 months old. I usually use it with Bluetooth headphones, however recently I have started to notice that when I start it (and before connecting the headphones) the speakers are cracking. And while they do so, no sound can be played. There is just cracking. This stops after few seconds and then the sound can be heard again, however without headphones the cracking comes back periodically. I have tried to reinstall the Realtec Sound Drivers but to no avail. To be honest it seems like there is a lose cable or contact inside since fiddling with the angle of the screen sometimes solves the problem for a while. Please advice on how to solve that.