Ken,

So, you are saying that the board/electrical components is the crossover?

If true, I see no evidence of burns/melting nor do I smell any hint of burned components... The wires attached to the board seem solid, no obvious cracks or breaks (at least from the board side).

Thoughts where to search next? I'm thinking of removing the speakers and checking continuity between the wires there, see if I can pinpoint a break somewhere. Seem like a logical next step?

Thanks.