ASUS GL703G gaming laptop issue?

As mentioned above I have a gaming laptop and I bought this back in September of 2018. Everything was working great until recently I have been hearing a strange beeping noise coming out of the fan hole above the keyboard. I took it to a pc repair store and they thoroughly checked everything but said there is nothing stuck in the fan and the laptop it self works just fine. But the strange beeping sound persist and I have no idea what is causing it. It isn't a loud sound unless you put your ear right on the fanhole but can anyone explain to me what it might be? Cause even the repair store had no idea. This is a picture of the fanhole: http://tinypic.com/view.php?pic=2zqsp4j&s=9#.XFZMslxKiUm After testing a little more I noticed something. If I put it on Power saver it doesnt make the beeping noise. But if it is on high performance the beeping sound is quite loud