Thanks for the tip. Sadly this would not help me. I have been using Track Ir for years and it is properly configured. I have it run with FSX, and DCS among other sim and it works flawlessly since ever.
I cannot identify where the problem is but the fact is that even when my FPS counter is showing 40 fps in some cases, my simulation begings to shutter a lot. The moment I freeze the Track Ir and start moving my camera with the mouse the shutter dissapears.
During one flight I manage to use my Track Ir about 60-70% of the time and the rest of the time I need to pause it and manage the camera with the mouse. I have the feeling that a number of users that have a performance / shutters problem may have the same issue but it cannot be identified unless they pause the Track Ir when they have such shutters.
I hope they can find a solution since this is an inmersion killer and annoys a lot.