Got the AVP back yesterday and was watching The Last Waltz before dark. It was a fuse.
Upgrades were done, mostly DTS related. When I have some time I hope to visit the Madrigal site and learn more.
No charge, my 5 years won't be up until late next year.
Madrigal just suggested I take it to my dealer, they're guessing it's a fuse. They did mention that there are two fuses and I should make sure both are replaced.
I believe you're correct about the five years and I can't put my hands on the receipt right now but my manual was published in 1998...