AVG above threshold, for hours??

[fotyc]

I have an app that warns me if any apps or system processes are above a threshold of CPU usage. The only time I ever get warned is maybe once a day when AVG is doing a system scan. However, today it's warned me every 60 seconds for the past three hours. Is anyone else having this problem? Should I try Avast instead? I pulled AVG off my PC because it was a total hog, Avast seems lighter in footprint.