I don't know, may be the computer need some settings may be you have to disable onboard audio in the Bios ?
Is it possible to check the UFX with another computer, a notebook or so ?

Such problems rarely have anything to do with CPU performance. You would have to validate that your BIOS and Windows settings are ok and if everything is set up well and the system has the lowest possible DPC latencies internally.
Also to ensure that not required hardware is not enabled / being used during audio sessions (access to network, bluetooth, etc). Try to find out in which situations the crackles occur and which driver might be responsible.

Or also: Are there perhaps dropouts due to network access ? Which sample rates and ASIO buffersizes are you using ?

You should also check the documentation of your motherboard to see if the USB card is in a socket where the PCIe lanes are shared with other components, which should be avoided.
You could also try to install the latest driver for the USb3 chip directly from the manufacturer.

But you would have to work through all this piece by piece in a sensible order and check here and there with LatencyMon and your application.

I don't have the time to guide you step by step, but you could at least provide some more facts, e.g. what kind of motherboard you are using, in which PCIe socket the card is installed, what sample rate you are working with, what your ASIO buffersize settings are when the crackles occur, how high CPU and ASIO load are and what happens when you increase the ASIO buffersize. Does it get better then ? What are the LatencyMon results and how do you measure?

What mainboard do you have Michael and into which slot did you plase the card ? Best is to use a PCIe slot where the PCIe lanes come from CPU not from the chipset and where the lanes are not being shared with other components.

And again the question. What sample rate and ASIO buffersizes do you use ?

Did you disable energy saving in BIOS and are you using the High Performance Energy Profile in Win10 ?

What are your LatencyMon results of a 5min measuring ?
Which are your 2-3 drivers with highest execution time ?

Please note: LatencyMon simulates already a DAW load while measuring. When measuring with LatencyMon you can use two different strategies
a) measure on an IDLE system (fresh bootet) no other system activities please
b) measure while working with your DAW

to a) tells you the basic DPC load of your system without running any other applications
to b) tells you the DPC load while working with your audio application

In both cases the drivers with the highest execution time is interesting to know.