When I first got my monitor the sound was working fine (the monitor has built in speakers), but now it no longer works. I can only hear sound if I plug earbuds into the pc tower directly. Though if I want to hear the sound through the monitor I hear nothing. I went into the sound aplication and it shows that the monitor is connected for sound and if I play a song it shows the little green icons, but I still hear nothing. The monitor is a msi optix mag27cq.