ccsvchst.exe uses 50% of CPU

Ever since the last update, Norton continuously uses 50% of CPU. 8 hours with online support hasn't fixed it. First one, and then another of the techs tries the same routine and it doesn't change anything. I've used Norton Removal Tool repeatedly and reinstalled repeatedly. Techs have done something with checklist and tried different settings for the software. One had me do a full scan. Didn't help. Is there any hope, or do I just need to get rid of it and try a different vendor?