I have had 2 Oazis z5 power supplies, both with the same problem. The power switch becomes increasing difficult to turn on or off. My first power supply switch died when the unit was under warranty; for the second switch I am not so lucky.
Both times the exact same problem, the power switch became increasing difficult to get to come on or turn off, until finally it did not work at all. It seems like this is a fundamental design flaw, and I hope Dolphin will address this issue.
In the meantime, it seems silly to pay $200 for a new power switch (supply) -- surely there is some way to replace this switch?