I learned about this problem the hard way last weekend with lighting for both a stage show and live event being screwed up by color source spots changing their DMX addresses. I had used them previously in other shows without issue so it caught me off guard. "I am very disappointed with ETC and their handling of this problem" is my polite way of expressing my extreme displeasure.
With the limited amount of trouble shooting we have done so far we found that sometimes the units would not change their DMX address until the third or fourth time that power was cycled. The problem occurred frequently when the units were being controlled through a color source relay, but did not occur when connected directly to the console with wired DMX. Also when we put the user screen of the fixtures into lock mode we did not get any address changes. All this being said, we have not done enough testing to make any real conclusions.
I was told there is a software update which will fix the problem. We will see.