The image above is a screen shot of my Rep History, in the space of 3 minutes a bunch of my questions were downvoted, particular 4 in one minute, 3 in another.
While some i could accept the downvote however some like "Do you import all Story Mode characters?" and "What are the requirements to get the floor jump?" i don't believe there was any reason to downvote them, also 7 of the 8 were the my most recent questions as such would appear at the top of my questions list, the 8th one i suspect was hunted down as it's was not a recent question which would explain the time gap
i suspect serial downvoting however i am unsure if the system had yet to detect it or if the conditions just havn't been met. so i am wondering is there like a scheduled time when the system picks this up or does it do the check every time a person downvotes?