I started having a problem 2 days ago when signing on multiplayer with FS Nav, The engine sounds on several add-on aircraft disappear. The two I have found so far are the Payware Grumman Goose and the PMDG 737. As soon as I try to connect to Multiplayer in FS Nav, off goes the sound. Select another aircraft,and the sound returns. back to the original, and the sound is off again. If I don't select Multiplayer in FS nav, everything is fine. The only thing I have done in the last couple of days is to install and then uninstall SB3. My question is, has anyone else had this problem, either with FS Nav and complex aircraft and or SB3?

Think I found the problem, corrupt FSUIPC