problem with cf or mouse? O.o

ok since when this new patch had update i was recieving alot of the client errors.So after they did fixed the client error i found 1 little problem and that is i cant drag shot anymore.here is the problem:
if i go to hard scope i cant drag fast.it moves so slow when i try to drag shot or quick scope.I have a good gaming mouse microsoft sidewinder i can change with a button on this dpi: 400-800-2000(that is max of it)
i never had before that problem but since the new fix patch i get that problem.So is it my problem because of patch or do i must buy new mouse because it works on other games pretty good. :S
Post comments and give advice because this is my main problem which i have when i use all kind of scope(including rifles scopes)

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