This sounds typical of ISP issues however, im not aware of AOL pulling any tricks like this at this time.. (doesnt mean they cant but I doubt thats the issue.)
If your running any third party software like MXMoni for auto starting turn that off for a bit and see it if continues.. Im not sure by your post above if you mean its only ppl that you are downloading from or if its everyones uploads that die off..
are you running as a primary or secondary? If primary I would also try secondary and see if this helps in any way too...
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