Sound Issues - FSD 337 Help!

I've just created a new box for FS9. It's only an i5 Core 3.32mhz box but that works well with FS9. So I went ahead and did a re-install of the FSD Cessna 337 and cannot hear the engines from within the cockpit. What's even stranger is that when I am in view mode, (Keyboard S), I can hear the engines from both directly in front and directly behind the aircraft. When I am viewing the aircraft from the side then it's complete silence.I've never encountered an issue like this before and would appreciate any assistance that you could offer. I am also going to post this in FSD's support area as well. I love this aircraft and would be very sad if I couldn't get it to work correctly for me. So please advise and thanks for the help!Mark