Midiclock Timing problem! Need help

I´tried to trigger a Groovebox (Machinedrum-elektron)with the Midiclock from Cubase. Start +Stop woks fine, but the timming ist not stable. I´ve recorded 1/4 klicks and there is an offset up to 250samples per 1/4.
Loops are horribel synced with Midiclock. Unusable! A Desaster if i tried to change a Pattern with a note command, every pattern changecommand the first note seems to be doubled with a short offset. Horror!

When i sync the MD with an extern SEQ or another synth with Midiclock all works fine and stable?
I´ve checked the options in C. :

When i disable the misiclock in C, and only use Strt and Stop commands to trigger the MD it works fine but after a while the drifting and splay.
It is impossible to record the pattern without offset. It works a little bit better if i start the song right from the beginnung and don´t stop it anywhere then is a chance it will works ok.

Any idea?
PC with no utiliazion, only the clock and the Machine.