No input signal on Logic Pro X (10.3)

All of a sudden I can't record instruments anymore via USB on Logic Pro X (v.10.3).

I am running Logic Pro on a iMac (Retina 5K, 27-inch, Late 2015), with macOS Mojave v.10.14.2

Strange thing is that I can see the input signal in the overall System preferences when I choose for the USB-device as input.

Also in GarageBand my guitar signal comes in loud and clear and I can record it.

In Logic Pro X, I have the same settings for input (USB Audio CODEC), but in no way I can get my signal into Logic.

I tried everything that was on the support page : https://support.apple.com/en-us/HT200260, but still no incoming sound.

Please help?