See screenshot No. 1 from the manual
And now screenshot No. 2
Do I understand this correctly? USB-3.0 UR44C ↔ iMac USB-3.0, is in reality only high-speed (USB 2.0)?
If so, sorry, I feel like I’ve been taken for a ride by Steinberg.
P.S.
And no, it’s certainly not the cable. Already tried several. Even original Apple USB-C cables.
No it is definitive USB 3.0, I have it connected it to a PC and it shows USB 3. Unfortunately I’m not in front of my system, so I can’t make a screenshot.
Hi JuergenP and thanks for your reply. So High-Speed is 3.0 and not only as written behind in brackets USB-2.0?
But in the manual
No, High-Speed is USB 2.0 as per the USB Definition.
USB 3.0 is SuperSpeed and the UR44C is 3.1 and that is even SuperSpeed+
Ashes on my head. Found out with the help of my son, it was the cable after all. Yes, I’m grovelling 
Many thanks for your support. It was definitely very helpful. Never dealt with it before either.
Hello…do you mean you are using now a USB C to USB C Cable…and the USB C Port of your Computer? I ve got the same Issue
Hi Andreas and yes C to C. But not every usb-c cable works. Not the ones from Apple, for example. They do not support 3.0, or 3.1. You should search for 10Gbps 100W USB 3.1 Gen2 USB-C.
My son said, take this, looks good it is thick. And he was right But if not I would go for to buy the one I mentioned.
P.S.
And what’s also practical is that many rightly criticize the lack of an on-and-off switch. If you go through USC-C, you do not need the 12V DC. This eliminates the need to constantly unplug. The power source switch at the back is much more convenient to reach
Sorry I’m late to this party…
Happy to see you solved your problem but I can’t resist to mention that using USB 2 or USB 3 won’t make an iota of (real) difference in this application.
USB 2 is plenty fast enough to deliver dozens of hi-res channels already, and yes, without noticeable latency. (latency bottlenecks are elsewhere in this chain)
USB 3 is “required” today only for marketing reasons (in applications like this).
The USB type-C conn. is sometimes useful because it can deliver more power than type-A, but not because it can support higher speeds.
