Problem with MIDI interface

Hi all, I have a strange problem. And I hope I’m asking this in the right forum. I’m using two ESI MU8 XL midi interfaces, both connected to their own USB port on my computer. So I have MU8 XL ports 1 -8 and 2-MU8 XL ports 1-8. I never had any troubles with them. But I decided to reinstall Windows 10 on a clean c: drive. I’m using Cubase 9.5 Pro. In the device manager of my computer both interfaces are shown. If I start Cubase and I want to add a MIDI track and choose a MIDI port for that track, port 1-8 of the first MU8 XL are not available, but if I disconnect the first USB interface and reconnect it, suddenly all the ports are available again. I never had this problem before my new clean install. I’m using the same, latest MIDI driver from ESI. Any Ideas?