Hi Scott,

Thanks for the advice.
I have two Eurolite Dimmer bars and they both do the same thing, separately and together. I have had the behringer desk replaced and the same thing still happens so I think it must be a fundamental mismatch between the Behringer desk and Eurolite products!

I have now sent the stuff off to a hire company who are checking out the signals etc for me. I'll keep you posted on the results