Surely it's not a problem of the scenery, and nobody ever reported it so far.
First, be sure you our AFCAD is the one in use. Which means, you need to be sure there are no other AFCADs for JFK anywhere in your system, save for the MS default one. You can use the AFCAD program to check how many AFCAD you have for JFK. You need to have only 2: the one from FSDT in the fsdreamteam\jfk folder, and the MS default one. If you have more, remove all the extra.
If the problem is still there, then it's probably a problem of your AI models, which have been programmed with the wrong radius. However, as I've said, many use WOAI, and nobody ever noticed this.
Also, check you don't have duplicates traffic.bgl files.