At first, I would've said this is impossible. But thinking about it, I might have a theory. It might be caused by a bad mains supply. For some reason or other your mains sockets are on largely different potentials and the current to compensate these potentials is so high that it actually burns down the hardware. Several ways to work around (though this should seriously be fixed).
- Use a multimeter to measure the voltage potential between the used wall sockets. If you don't know how to do it, ask an electrician.
- Use the very same wall socket to power your Amiga and the router.
- Use a cheap hub/switch to protect expensive equipment.
- Use a UTP network cable, the shield of STP cables runs the compensation current.
BTW: Have you checked/swapped the A1200 PSU? As a constant, it might also be the problem.
