I Can't get the machine to do the speed I'm writing in the INI file

Hello all!

I've been encountering a problem for a while now on linuxcnc. My project is a Linear Delta Robot used for milling. 
My problem is, when I run the configuration file on any G-Code, the speed of the motors is slow no matter what the speed I'm putting in the INI is.
And also, when I'm setting the StepConf file, in the test-axis section on each axis the motors seem to be working perfectly in terms of speed. But when I run any G-code on the same configuration file, the speed gets reduced so much. 
Another problem is an error I get quite often, which is, joint 0 has a following error. I wish someone can guide me through this error.

And thank you.