Solved PC crash when powering on M Uno - possible Voltage drop / high initial current?

Hi again,
powering my M Uno on causes the mini PC to crash (and restart). When M Uno is powered on, after a PC restart, no issue.
I got aware of this when searching the reason why the Pegasus UPB2 looses connection....

Setup: 12 V high quality 10A power supply, all plugs checked, short cables....

@ Avalon: can you provide informations concerning the initial current when powering on a M 1?

does anybody else experience this behaviour ?

thanks
Peter

update:
there is a significant voltage drop and it is due to the power supply ("Leike 10 A quality power supply") - I compared with other power supplies as well as with my big accu and had no issues.
The power supply in question activates its short-circuit-protection (when pluggin in the M1), shuts the power down and then raises the voltage slowly.
As far as I could measure the current the M 1 initially causes a certain peak current (below 1 A) which is interpreted as a short circuit....
It is a LEICKE 120W power supply - so if anybody thinks about buying this one be aware.....
cs
Peter