Problems with audio volume

Em_54

Today it happened to my that after leaving the pc for a couple of minutes, the sound of the game seemed very very low, making conversations, music and effects barely audible. Exiting the game or restarting the pc seemed to resolve temporarily the issue, but has happened around four times now.
During the last few days it never happened. Any idea how to solve it? Thanks for your time.

dr_io_ESO

Same happening here, I noticed that my 5.1 creative system center channel lost audio causing the reduced sound