A customer has an IPOV2 cabinet with 2 expansion modules for Norstar phones, DS30A and DS16A. I have had a problem with the DS16 losing signal with the IPO and not coming back up. I was finally able to get it back up by putting it in a different expansion port, but it was not an easy process. Our distributor has an open case with Avaya, but no once can explain why this happens or if there is an easier solution. Any thoughts?