Something destroyed my design

Not sure it’s Estlcam or ghost in the machine somewhere but I prepared this design today:

And the (first) result was this:


The router bit just went straight through the O symbol and took away bottom of E and P letters.
It looks as if the curved part in the O was intentional.
I tried again with the same file but this time I upped the speed 10mm/s and cut only half the previous depth and now it went better (almost finished in the image):

A bug, but where? And how?
Estlcam 11.245_A_64

Are you running it off an SD card or using a gcode sender over USB?

SD card. Had too much funky behavior with Repetier host