I have a fairly new computer, about a year old and it has been working well. A few days ago the sound started changing, In FS9 and in FSX, The engine sound became louder and some of the sound quality was lost, when you selected flaps it nearly blows you out of the room, and now ATC is faint you cannot hear what they are saying. It does it with all the planes I have installed. In FS9 and FSX in the game I set ATC to 100% and turned down the engine sounds and cockpit sounds and environment and all that but it still does not make much difference. Still can't hear ATC. I went into control panel and tried all different settings in Sounds and Audio devices,  and still the same. I tried my wifes speaker system and earphones and still the same. I tried to put in new sound drivers but it said the ones I have installed were the same as the updated ones.
Could anyone help me on this problem, I am at a loss of what to do next.
My computer and system is as follows:

I am running 3- 26" monitors with triple head to go and the head tracker.

Windows XP Professional 32 bit
3.0 over clocked to 3.54 GHz Intel Core 2 Quad Q9650 Quad core processor
EVGA 750i  SLI Mainboard 1600MHz FSB
4GB (2x2GB)Corsair Dominator XMS DDR2 1066MHz
IGB EVGA GeForce CTX280 GDDR3 Graphics Card
1000 Watt Approved SLI Power Supply
20x DVD+/RW Optical Drive W/ Light scribe
500GB 7200  32 MB HD
High Definition 7.1 Integrated Audio
Realtek HD Audio
Any help would be appreciated, Thankyou
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Ok, Thankyou for your help,I'll try renaming the FS9 Cfg like you suggested and see what happens. Sometimes these computers can be very frustrating, they do weird things for no reason.
Thankyou again
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