I can state from personal experience that even something as loud as a fighter jet doing five hundred or so knots a couple of hundred metres away is not noticeably audible over 30kph paraglider wind noise until a second or two before it passes.
Once it's past, then you can hear it, but it's a bit late then... and also, you're a bit busy dealing with the wake turbulence.
Biting the hand that feeds IT
