FSX Sound Issues

Hi All,

I've recently come across issues with my sound within FSX. For example, when starting from cold and dark in the PMDG NGX or even the default Cessna, I seem to missing the battery sounds with them only playing if I click on a switch for about a second and then it cuts out again. I'm having the same issue with the FSL A320, where I'm missing the dynamic sounds such as the engine's windmilling etc.

Any ideas? I've tried a fresh re-install of FSX and I've just done a re-install of FSX, My OS and my drivers. 

I'm running 64 bit Windows 10 on a Z170 Pro Gaming.

Kind Regards,

James Roberts