problem with audio on mac OS X Yosemite

Hi;

I have a macbook pro 2013 release. Since i upgrade to OS X Yosemite I am facing troubles with my Audio.

On attempt to connect any headphones to the laptop during a playback of anything ((i.e. movie, audio)) with all apps ((Vlc, quicktime, iTunes, etc...)) the is no sound heard on the headphones. Change to different types of headphones and again I got the same result.

If I connect the headphone before playback ((i.e. no sound released from my mac)); i can only then manage to listen to the headphones.

searching on net for solution i attempt to access "Audio MIDI setup" double-check that the sound output is set on 44100.0 hz but still the problem appears. I can't find a solution so far for...

Does anyone suffer from a smilier problem!!?