hello guys, i experience following problem and hope you can help me:

- when "legacy USB" is activated the system boot takes a long time and shows Code "B4". According to the product manual this has to do with "USB hotplug"
- In UEFI gui my mice (Steelseries Xai) does not work. I can't move the mousepointer at all and have to use my keyboard (Microsoft X4) to make some changes
- only solution I have found is to disable "legacy USB". Changing the option to "UEFI setup only", "enable" or "auto" results in error Code B4 again and long bootup time.
When legacy USB is "disabled" Windows boots within seconds to the Windows logon. But I can't get into UEFI again... :-/

Is there a problem with my board or is this an UEFI bug that can be fixed with an update? I am using Bios Version 1.7. Thx in advance!