Default LG L9 II D605 - Speaker problem..

Hi,

Im new here. 2 days ago i bought LG L9 II (Kitkat 4.4.2. branded) and im having issue with the speaker - there are something like interference, noise of varying intensity. (like from PC speakers if u put ur phone next to it) during a call. Any one having same problem? Its software or hardware issue?

It was just 2 days and Im having problems now im thinking about changing this phone for L90/g2 mini....