X-keys Pro problem

Long time lurker, site has been a huge help getting everything going and it's been smooth until now. I'm having some weird problems with my X-keys Pro. Ive got some basic macro's programmed, such as..

/assist focus
/cast fireball

yet when I hit the key on the X-keys Pro sometimes 1 or 2 of my mages will start casting while the other jumps to the left, puts up the inventory window, or gets and invalid command error. While the next time I hit it only 1 mage will cast and the others will freak out, or I may hit it and all 3 will cast right. Anyone ever have a problem like this? It's obviously lag of some type just know sure where...or how to correct. PC's are C2D 2 GHz chips with 2 gigs of ram, 7600GT's 256 video cards so I don't think thats the hold up, ping is in the green... I've opened notepad and hit said keys over and over and each time the correct macro commands are being typed into notepad correctly at the same speed so its not that the macro is being sent incorrectly. Is there anyway to minimize the input lag on WoW any further or slow the X-keys down? It's just in WoW, looks like it may drop the "a" from assist or a letter from which ever command I send and I get "type '/help for a listing of a few commands". Any thoughts would be great.

My set up is as follows...


X-keys pro plugged into a Vetra keyboard broadcaster which is then connected to 3 separate PC's with above specs, 1 for each mage.

Sorry if this has been addressed before. I didnt see any other post like this, I will continue to look.

.......

Are you programming keypresses (alt + f5) or entire commands (/follow Xzin) into the Xkeys?

Because the second will not work. Well, it will. But not very well.

Use the in game macros.

Yeah use the ingame macros. :)