John Bowers Active One Speaker Problems

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Hello,
I recently acquired a pair of John Bowers Active Ones,
serial number 359 and 360. Made in 1985.
They have an internal 300W Mosfet amp.
So I get them home, plug them in, run an RCA jack from
my preamp and get nothing - no sound at all.
One the back, they both have one small red light, and one small green
light, both are on.
When I first turn them on just the red light is on, then I turn it off,

turn it back on a litle bit later, and they are both on.


1) I open the case and look at the amp boards and it looks like the
preamp board (tone control I guess) has a small black smoky looking
spot, so I'm assuming it's fried?


2) The power supply says 220V, and it was sold originally in Germany,
could it be a power supply problem? Could US power have fried the amp?
It uses a computer style three prong AC cord.


I ran the speaker connectors out the back and through an external
crossover and all the drivers are working perfectly and sound great
with my tube amp so it's not a problem with the drivers.
All the fuses are fine.


Any help or suggestions would be greatly appreciated.


Thanks,
Mike