ArtDmx: send and receive?

Hey

I have been trying out ArtDmx with GrandMA and im having a little problem. When using the Sender and Receiving at the same time as a VDMX plugin, the Artdmx seems to send zero values every now and then, and that makes the lights blink?!

Anyone know how to fix this problem? I read somewhere about putting a switch in between the signals, sadly I don't really have the budget to buy one right now just to try it out...

Cheers! Niku