Trying to get to the root cause of it would take more time and Solarwinds support might need lots of things to fix the same. In parallel what I would suggest is (I am considering all odds being exempted in this issue - like upgrade, new patch installation on the server etc etc. If nothing was performed on the poller recently then go with the below suggesstion)
Check what all servers have been added to this poller of yours which has an issue - check health of the servers added to it, including SAM app monitors that have been applied on these servers. Try and get rid of all Unknown and Down (as many as you can) , once done restart services on that poller and check CPU utilization again.