I'm now running HeliTraffic and have no problems with my ai traffic.
I have ATX (if that matters) but it's disabled.
Do you mean FTX AU Traffic? I would guess this is causing your problem.
After installing FTX AU Traffic you have AU Traffic but the default traffic is disabled. You can turn the default traffic back on using the FTX AI Control Panel, which should have a shortcut on your desktop. It's all explained in the FTX AU Traffic User Manual, shortcut also on your desktop.
If you disabled FTX AU Traffic in the Scenery Library only, the default traffic file is probably still disabled. You can check the ..\
\Scenery\World\scenery\.. folder for the trafficAircraft.bgl file. If it's still named trafficAircraft.bgl.DISABLED-FOR-FTX-AI you can run the FTX Control Panel or simply rename to trafficAircraft.bgl to get your default traffic back.
Having fun with my HeliTraffic :grin
Dave
At that time [1909] the chief engineer was almost always the chief test pilot as well. That had the fortunate result of eliminating poor engineering early in aviation.