Distorted engraved text

I have a small 3 axis desktop mill - Sable 2015. I use it for pcb work and small wood jobs. I have been trying to engrave pencils with text with a height of 2.5mm. The typeface is a single line font called Railway1L, I use Cut2d to generate the code for Linux cnc. Stepconf is configured with data from the Sable 2015 Web page with values of 13.4mm/s for max velocity on all axis. Max acceleration is 150mm/s/s on x and y and 100mm/s/s on the z axis. I use an engraving tool with a feed rate of 6mm/s. This cuts without difficulty. The text however is badly distorted, an E for example has a back which is a curve. N and M fail to start in the correct place. I am happy that I have the correct g code, if I single step through the code it works perfectly. If I reduce the feed rate to 2mm/s it also works OK. What seems to be happening is linuxcnc is issuing a new command before one in progress is finished. I imagine there has to be a way of telling linuxcnc that it needs to wait a bit longer somewhere. Can anybody suggest where? Please keep your answer simple please!! I feel sure that the mill is capable of working at 6mm/s without difficulty. Please could you also advise me of the best part of the forum to look for answers.

Have a look at G61 etc.
linuxcnc.org/docs/2.8/html/gcode/g-code.html#gcode:g61

Thank you, problem solved. Many thanks for your assistance.

thi INI file has a STARTUP Code
so the mashine is on G61 if you put it there
but it is better to get your postprocessor to the right output
so everything on G-code to tell the mashine state shoudt also be in G-code
Starting With G17 for plane
Metric or inch
Main Workpice coordinate system to use G54
Precision G64 /G61
absolut G90
set the Cycles off G80 G40 G49 ..
Then its time to set the G-code fpr your part this shoudt be always the first thing to get a postprocessor g-code for your mashine