However before pursuing that any further, try increasing the ASIO latency to 512 samples using the Komplete 6 control panel and listen to what happens.
Done, the same clicks!
Assuming the problem persists, if you have onboard sound like a Realtek chip, try using SONAR with MME (you'll need to set the latency for at least 50 ms or so) and listen whether there's the same click. Also if possible, borrow a different interface and see if that solves the problem.
I already tried my old US-122 Interface: It works with win10 without clicks!! The only issue is, win10 cannot shutdown when interface is connected.
I very rarely think hardware is the issue, but the fact that you get a click with any audio operation does make the interface, or some other element of the audio chain, suspect.
Thank you Anderton for your note to give a new try before i buy a new interface.
Here is a new solution:
1. I deinstalled the US-122 driver
2. I reinstalled the Komplete Audio 6 driver
3. The same clicks/crackles despite various settings!
4. I downloaded the last Asio4All driver (2.13)
5. I installed it (without deinstallation of KPA6 drivers!)
6. It works! No problems with clicks!
The only thing is, you can use only one set of input/output. In my case input 1-2 and output 1-2 works. The settings in Sonar for KPA6 are greyed and not selectable. So i can't choose 3-4 and the digital outputs 5-6. I don't need the other in-/outputs therefore for me is the solution ok.