Audio too loud (Speakers)

Whenever I enter a video or any program that makes sound, the volume rises a lot and then it decreases automatically. For example, when I open a video, and my speakers are at 40%, it sounds as if they were at 80%, and then after some seconds it lowers down until it sounds at 40%. I don't know why this happens, 1 week ago Dell recommended me to update my audio drivers, and since then I've had this problem (this didn't happen before the update). I've deleted and reinstalled the Realtek Audio driver but this doesn't work. My laptop is a Dell G5 5587. Help please, it's really annoying.