I have an AC 3.0 system in my house with six euro6 phones, and one euro 18D phone. It's worked fine since I got it about 2 years ago or so. This morning I walked into my office and the 18D is dead, no lights, no display, and when I pick up the receiver I hear nothing. The 18D is of course plugged into ext 10.
If I plug the 18D into another port it is still dead. If I plug any other phone into ext 10 they work just fine. Even my old MLS-12D which is kind of flaky and yellowed works.

I took it apart and there are no obvious components that are bad. Any debugging clues here? There are two bridge rectifiers inside, and both are producing a DC output.

Any help is appreciated before I plunk down some more cash to replace it... :-(