I have been experiencing performance problems with NAV (version 16.8.0.41) for a while now. The symptoms are that I leave my laptop for a little while and the idle processes kick in - a little while later I will hear the CPU fan start up - if I then start using the machine, the machine is sluggish and remains this way for about 20 minutes. 
Closer examination shows that it is Norton that kicks off it's Norton Insight Submission process and that this runs for about 22 minutes. The CPU graph shows that the machine is no longer idle, but the process is not stopped or suspended - it runs to completion. See screenshot below.
My machine has a dual core processor, and Norton hogs 50% of the CPU (i.e. one whole CPU core) for the whole 20 minutes. This happens usually once a day!
What does Norton Insight Submission do and why is it so processor intensive? I am guessing it is not supposed to be as CPU intensive as it is - so is this a known bug? Is there any way to turn it off?
Thanks in advance,
Robert