Hi Nic,
I have installed the driver manually but this did not fix the delay issue. There were no warnings this time.
The warnings (not error messages) only asked me whether I trust the manufacturer of the software and at the beginning of these several pop ups I had to grant administrator rights. This happened after I've installed the driver by executing "setup.exe".
I had this issue with Intel's USB 3.0 driver before and it was solved by "trusting" the source of the downloaded zip file. For this I had to right click on the zip, open "Properties" and click the button next to the warning "This file is downloaded from the internet...".