Recently I found out that despite I do hear sounds from any other sources , like ambient , voice , parcel audio etc. when I try to use any media display , like a youtube player, I can see the video playing , but there is no sound coming out of it .

According to the viewer settings , media is enabled ( wouldn't be able to see the video playback otherwise).

I looked if in pc I had some output muted in windows sound mixer , but nothing is muted .