My suggestion would be to never use Norton.
McAfee, Nod32, Kaspersky, BitDefender are all great antivirus programs that don't hog your resources. Also run periodic antispyware scans with software like Ad-Aware or Spybot.
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For my dreams i hold my life...
I miss my Meizu M6SL... Currently rocking a Sony Ericsson w595 on Samsung in-ear phones. Does fine, but it's not a chipod...