Shifting layers?

I’ve had the K1 for a year now. 3 months ago I had to change the extruder circuit board and that’s how I installed the successor model of the extruder.
Everything was working great until 2 weeks ago. Suddenly I have shifts in the layers in the middle of printing. Is this perhaps a defect?
If I had changed something I wouldn’t be surprised.
I tried this with different filaments. Always the same result.
Any tips? Or does the K1 only last for 1 year and is then so worn out that it causes such errors?