viz crashes console Stack Collision!

[gym1339]

I have a show on my viz that locks up my console the moment I engage the Rs232 connection, I receive a Stack Collision error on the LCD; what is this? When I power the console off and on the Lcd scrolls continuously(if the Rs232 connection is still engaged in the Viz) and I have to pwer dwn and pwr up holding 21-30 flash buttons to enter Avos.
Everything works fine if I delete the dimmers in the patch, so that's where I started working. I have narrowed it down to: if two dimmers are patched to one handle, this seems to be the problem. Is there anywork around this other than programming with the movers and adding the dimmers latter?

Thanks,

JIM