Login to the web console as an admin.
Click on Admin > NTA Settings > Settings > Edit Applications and Service Ports.
Expand the Muti-Port Quicktime Applications and Edit the default Port Range 6970-9999 to exclude the port 8080. You can e.g. add 6970-8079,8081-9999. Then Click on Update Application.
If you see some conflicts, edit again the port range to exclude the ports already used by different apps.
Once done, Click on "+ Add Application" to create your proxy app.
NTA will correctly identify your Proxy traffic only for the new collected traffic. Data already collected will not be reindexed (I think...need to make more tests to be sure, or simply give a feedback once you made the changes :-).
Spot on thanks, traffic is no idenified correctly. Looks like the traffic previously identified as Quicktime application is not re-indexed.