Sound problem

I posted this in the FSX forum but no takers.....I am getting desperate!I thought I had this solved but it has reared it's ugly head again and has an added dimension. Upon landing I get a one stutter before touchdown. I had that before and started using Nod32 and that went away. Now that it has returned another sound stutter has started. When an ATC window pops open to talk to me it will give a stutter....when I close the window and ATC is talking to another aircraft I am also subject to get the stutter. All of this happens around 75 percent of the time. I changed sound cards....turned sound off...disabled sound card...still happens...even though there is no sound but when there is supposed to be sound...landing and ATC. I am clocked but went back and set everything back to default and still same. I am on Asus P6T Deluxe...6gig Corsair mem....i7 920...two 500gig HDD with one dedicated to FSX properly defragged and setup using Nicks guide. This just showed up...all was running well. I do have wireless mouse and wireless joystick. Type of aircraft makes no difference. Any suggestions would be appreciated.Regards