This is an update to my earlier question: I can use existing building wiring through the AVB switch between a console mixer and a rack mixer. However, my stagebox will not not connect to mixer over this same CAT5e. It will connect to the switch on a short wire and the mixers work great. I knew 10-year-old building wire might give me trouble but I'm puzzled because it works mixer-to-mixer but not mixer to stagebox. I did update firmware on all equipment.
Thanks for any suggestions or insights.