ACME IM 250 S and K8062 problem

Hello
I have four moving heads ACME IM 250 s.
I use the moving together with the Velleman K8062 USB DMX.

This moving exhibit a strange problem:

  • When I use multiple devices together with the moving (par led - strobe - smoke machine - par64…), at a given moment the dmx signal is cut and moving go to state BLACKOUT.

When I use the moving to the programmer’s desk acme another problem occurs:

  • When I’m creating scenes, press the MIDI / ADD the same problem occurs, that is, moving the state to try to go BLACKOUT. but after you finish entering the scene moving back to work.

I’ve tried all solution types indicated:

  • terminators
  • Dmx cables correct
  • Moving the splitter for use on a separate line of other equipment
    Nothing solves the problem.

Interestingly, the problem is random, not repeated in the same condition.

All other DMX devices work properly. Only the moving heads have this problem.

I’ve tried to qualified personnel but they can not explain the problem.
So I’d like you to indicate me a solution or where to find who could give me help.
I do not want to sell moving to buy other models as already used in my other system and moving to work correctly.

Have you ever had this problem?

I need urgent help.

Thanks