Mark,

I had built a twin PSU for the Caiman one set at 12v and the other at 5v. I tried to swap out the Murata's and feed the supplies straight in. Had to reverse engineer it though as just could not get it to work.

The 5v supply drops to 4.3v under load (connected in at the same place as the Murata output pin) and I was too scared to up the voltage back to 5v.

The whine was there before I did all this though.

Regards