OK problem, I made a nice, 3d printed case to hold my mac mini. but have a real hard time putting the SD card in and out. So I bought an SD card reader extension. The problem is it only reads it when I plug the card into the extension, then plug the extension into the mac. If I leave the extension plugged in and just plug the card into the extension the mac doesn't read it. Do I have the wrong extension? or is there any way I can leave the extension plugged in and just the card without unplugging the extension each time? it makes the extension useless if I have to plug it into the mac each time. thanks