Sound problems and stutters in FSX

[mark turner]

Hi all, New here , been a simmer for a while, but been flying Falcon4. I have been seduced by the fantastic screenshots and got FSX. In addition, I have the following add ons:

REx, GEX Usa & Canada, UTX usa & Canada, ORBX Australia, FS Global 2008 and the Aerosoft F-16.

I have spent loads of time reading up on settings and install procedure and have just done a complete re format and fresh install of Windows Vista 64 as it was recommended as being the best and most stable platform for FSX. I have installed the sim exactly as recommended in NickN's excellent thread on this subject, including all the de frags using O&O defrag.

The sim runs pretty good, I have only added 3 things to the config file, the affinity mask 15 for quad core, set TBM at 80 and widescreen to true. I have the latest Nvidia 64 bit graphics, and set them up using Nhancer as per NickN's post on the subject.

BUT !!! I do have a small problem. When I am nearer the ground or near clouds, I get sound interference and crackling, coupled with fluctuating frame rates and stutters. Thes are not terrible, but on takeoff from YMML airport in FTX, my frame rates go down to single figures. Its better once aloft nad I can get a steady 30 in normal areas.

Does anyone have any suggestions regarding this? Do you think it is a sound setting or driver issue, or just the system struggling a bit? In which case, what is the first thing to look at?

At the moment,