Well...the crisis has been resolved. After unplugging all...yes all connections under the dash, it turns out the leveling jacks control panel was locked up. It was the buzzer from that same panel that was making all the racket. Well after unpluging those connections and reseting that panel, the siren was silenced. I've read alot about gremlins in these dash panels, and I guess this was just one of those, because everything appears to be operating normally now.
'05 Itasca Sunrise 33V