Premiere Pro dampens / drowns the music while the editing

[Pamplemuss]

Hello, my questions is maybe a little bit strange -- but Premiere Pro dampens / drowns  the music that I listen during the editing. I listen to my radio or player or whatever, and as soon as I launch Premiere Pro and open it for work, my music automatically becomes 20-30% of its normal volume. Even if I mute all audio tracks in Premiere Pro, it's still the same story. Anybody else encountered this ? Anybody knows how to fix it ? 

Thanks in avdance,