I'm an AMX programmer (and Crestron as well). I can tell you that A LOT of the time the A/V LAN is a completely separate system that isn't physically connected to the house network. But that is no excuse for leaving a backdoor. Of the two major competitors in commercial control (AMX and Crestron), AMX is usually considered the most secure. They put a high focus on security so that they can land these government jobs. Just to give you some background, Crestron controllers currently run embedded Windows and previously ran VxWorks. AMX controllers previously ran VxWorks and now run Embedded Linux. The AMX controllers have many levels of security including a DoD mode which shuts down most of the services (FTP, web, telnet and leaves SSH). Their proprietary communication between the panel and the controller (carried over port 1319 and registered) is also encrypted in secure mode (this generally carries button presses, text updates, levels, etc.). Sounds to me like the engineers didn't want to give up the backdoor account for service issues once it was discovered and likely didn't realize what a big mistake it was by the time it got passed down. I've met most of the people at AMX and they are very good guys and gals. It's an engineering driven company (not marketing driven). The Harman acquisition may change that to some extent but they are true geeks who I am sure realize they messed up. It's a small company (aside from the Harman parent) in a niche market. They will learn from this and move on.