Default [Q] SM -N9005 International model sound problem

Hi

I updated my SM-N9005 International non-rooted model to official Android 4.4.2 over Kies3.
After the update my device is putting out sound from its loudspeaker and headphones at the same time. It can not be an application problem because I have tried different apps (PlayerPro, MX Player, Samsungs native music player and other media playback apps) but the issue is still there. After a restart its fine for the first time I use an app and after that it starts butting the sound out from the speaker and the headphones again.

Does anyone have the same problem?
Has anyone found a solution?

Thanks in advance!