I couldn’t solve it since my original post…
The problem is that my devices are still not recognized in Win7 (no OB involved just as plain usb devices). I uninstalled everything but some components of the AR’s and A4’s drivers probably remained installed (nothing is shown in the device manager though) so it doesn’t start installing fresh drivers when I connect them. I don’t even hear that system sound what Win makes when you connect a new usb device. Do you maybe know how I can delete and uninstall everything related to AR and A4 in Win7?