Problems with engine sound

Hi There,I'am having some problems with the engine sound on the PMDG 600/700 I can hear all the other sounds except for the engines! I have checked the box of the engines in the sound menu even put it on 100% but still no sounds heard. The strange thing is that when I go from 2D panel(where I hear the other sounds only) to the Virtual cockpit I hear nothing at all. Does somebody got the same experience or has anyone got advise? I have got the same problems on other 3 party aircraft and I didn't had this before untill some days agoThanksJarno Deken