Ok, that might be part of the problem.
If you don’t need spindle speed or feed rate over-ride then I suggest you load this version of grbl on your machine. Since you are using PEP6 load in the version with the 1ms Dwell.
If you use Vectric products go ahead and pick up the post processors that are available on that page.
We can make 1.1f work if you need those functions.