Big thanks everyone, particularly Jon, the resistor and mic loaners were greatly appreciated!
No improvement in the static and bricking though, Jon thinks it's likely the OM1 not being able to deal with the 661 p48 noise. Just one of those things, no ones fault. They do work with my 148 so rather than sell that as I'd thought of doing, prolly just keep the brick and the mics for a while. Weirdest damn thing, never ran across this before running mics directly into a phantom powering deck. :face-palm