Are you sure it's actually the power supply?

I replaced the power supply in a G68 and it 'failed' again after a few months.

On further investigations, it was the metal contacts in the plug that plugs onto the power supply pins, one of the 5v contacts was carbonated and black.

I bought some better quality crimp on contacts, refitted them to the cable, plugged in the 3 month old 'failed' PSU and it's been fine for the last 4 years!

Main: 861v4, UHD722, 558, Klipschorn, SVS PC13u
second: Tom Evans Eikos, DCB1-pre, DIY Nelson Pass PLH amp, DIY speakers.