"100% of at least 1 CPU USAGE" help please

i get this message with norton antivirus

"100% of at least 1 CPU USAGE" in reference to BF3.exe (battlefield 3)

please help, system specs below

 

norton internet security essentials


Intel i7 2600K CPU
GA Z68X-UD3R B3 motherboard
2 x 4G Kingston 1333mhz
1TB Seagate SATA 3 ST31000524AS _ 120G SSD
gtx 590 gainward 
Cooler Master Sileo 500 silent case 750W power
24" monitor
DVD RW
W7 HP 64

Regards