I use
Steinberg CMC-AI
Console 1
Nektar panorama P1
and Behringer USB mixer.

The nektar has been going mad and freezing up. uninstalled and re-installed its drivers and noticed my Behringer USB mixer driver disappeared, so i re-installed that. Got it going …kinda

Anyhow my question is, can I have too many usb controllers and devices which are causing chaos in my system or should they all work fine and in harmony?

I am on PC with Cubase 9.5

Thanks in advance.

They should all coexist fine.
Just remember to have them on separate midi ports and exclude them from All midi in.
I have a lot more controllers going without any issues.

Thanks for your comment.
They are usb don’t use them for midi. The only midi I have active is my keyboard.
the rest are not activated in the midi port list. If i should have them active, how do i assign them to different midi ports?

Well, either you use different midi connections on the case of the computer (if you aren’t already), or if you want to take it further you check the block diagram of the motherboard and make sure that the USB connectors lead to different USB controllers.

On my motherboard for example there are connectors that go straight into my CPU, then there are ones that go through a different controller.

You could simply just move things around until it works fine.