Again, it is not loud, but it is distinct. Here are couple of screenshots, maybe that will explain it better, taken in noisy environment (AC running full blast), green lines are instantaneous so they move a lot, the magenta is averaged : Noise measured at the top vent: Noise measured at arms length, where I sit: Monitor off, same position as above: That spike at 6k in the middle picture is what causing me headaches. Objectively, this monitor is not loud at all, but it is annoying as hell. Like a fly in a bedroom when you're trying to sleep.It is not like I'm imagining things here, it is clearly visible in the graph. Since you're a pilot, do they ever give you some kind of a chart showing how you respond to different frequencies, or is this just pass/fail type of test? Could you open the service menu and check what is your die temperature?