From the testing I've done, jamming a PS2 adapter on the end doesn't work and I'm sure I recall Jens (the designer) saying a PS2 adapter wouldn't work. Considering the Keyrah has an On/Off switch I suspect it is a power issue.
It has nothing to do with power. PS2 adapters don't actually do anything but adapt the plug. For a keyboard to work with one it has to support the PS2 protocol and the Keyrah doesn't.
