[SAS~CirX]

that sound like a buttons problem. what aircraft uses what engine sounds come from the buttons file. So do a search of your entire IL2 folder, see if there are more than one buttons lurking. then go unpack AC installer 3.8, and go make sure you select the buttons for UI, and replace yours with it. Also, check if you have installed any soundmods over your UI installation, like SFX, or English Sound Mod or whatever.