Since I suspected that the Z axis was loosing steps during printing, I swapped the driver around with the X axis where, while printing, it is much easier to see if steps are loosen, simply looking at the result of the printing while progressing.
I detected that the driver on the X axis (ex Z) was the problem because visibly losses steps (the printing was moving away from the original position). Now that I have found out that the problem is the driver I also experienced that the one from X now on Z has been damaged. I think I have a problem on one of the motors on the Z that damage the driver.
How do I check such motors to make sure they are fine without incurring the risk to damage additional drivers?