What's probably happening here is the default rule looking for excessive Web Traffic from the same system needs to be tweaked or disabled for your environment. (Congratulations, you see a lot of web traffic!? )
The rule basically says: if you receive more than 10 web requests from the same person in 10 seconds from the proxy server/content filter, escalate it to suspicious activity. The 10 in 10 seconds might need to be higher (or disabled if you don't care about that sort of thing). This rule lives in SolarWinds Rules and is called "Web Traffic Content Filter Infer HTTP Client Access alert". You can disable it there, then clone a copy and tweak the threshold if you want to keep it around.
Thanks very much that's exactly the type of answer i was looking for, the site does get a lot of hits so this helps explain it, i will try adjusting the thresholds to begin with. Thanks very much for responding, i searched high and low and couldn't find any more info on this alert.