There is no engine sound in FSX SE for any plane I fly. If the volume is turned way up then the wind and brakes can be heard. I don't know what caused it, but about the time the sound went out I had downloaded the latest update from Nvidia ( 3.3.0.95). I've tried deleting the FSX Config.and going through all of the audio drivers un-installing then re-installing. I have Windows 10.

have  you tried  pressing  the  q   key   twice  once  to turn  sound  off  and  again  to turn it  on it was  a fsx  quirk   dont  know if it  relates  to fsx.se  though worth a try

I've pushed the q key and when I do I see the sound off/on at the top corner of the screen. No, that's not the problem. I've tried a system restore, but twice it was unsuccessful to get the restore point.

Can  you  roll back to a working  nivida  driver that worked  since  the issues  seems  to occurred  when you updated  to  the latest  version, best bet  if  you have  a good  working  driver  is  not  to update  ti

I rolled it back to the earlier version and it worked. Thank you so much.