That's very interesting but I really don't understand how the CB200 could care if one of the receivers is an Assist ? Is the Assist fail-safe setting the problem with intelligence fail safe from an Assist preventing fail over to Rx2 or Rx3 ? If so I was under the impression that the latest Assist firmware had that fixed and you could have the Assist output noting on Ex Bus (assuming stabilize EX Bus is selected for CB200) and if the Assist goes to fail safe it outputs nothing so the CB200 can fail over to 900Mhz, etc. What am I not understanding correctly ?