More Details needed from yous side:
* Laptop or Deksktop?
* 15 or 22in1 Media Card Reader like in HP Modells?
HINT - Monitor all PNP and Removable Media. Open the CASE of the Desktop (If it's a desktop) and then UNPLUG > Internal on the mainboard the USB Cable TO the Media Card Reader.
Check the events that will generate > This will lead you in the right direction. With laptops more complex.
You will spend many hours when not days on this one. Consider removing the MEDIA CARD Reader as options first (Hang it off internal on the board) as option....
Find out first how many clients and which readers and if it wouldn't be easyier to drop the card reader....