Some success with Hardware acceleration.  I first turned acceleration off in DxDiag and still had the repeating guns.  Then I turned it back on and I got single shots stopping as I should.  This works until I exit and re-enter FSX and then I have to go through the steps again.

I have Realtek HD Audio OMB and tried changing the driver but with the same results so I rolled back the driver.  

It is only a temporary solution or perhaps a clue to the solution because I don't want to repeat this process every time I load FSX. :(