midway MK2 cab issue

just got a mk2 cab that was converted to a primal rage a long time ago..
anyways, the power converter(?) seems to be making a a whine/hissing type noise (sounds like a mini fridge) which seems to be making the screen slightly garble and the speakers sound static-y, do i need to replace the power swich or is the possibly a bad connection somewhere, or does it tie in to the main power supply?

my plans are to get this thing back to MK status in the long run btw

Are your sure it is not the monitor making the noise ? If it is the psu you would be better off just replacing it.

With the MK2 board set you will need the -5 volts for sound.