Steve76,
I had heard rumour that the A-Star news copter was subject to the pilot mistakenly selecting the hyd test button rather than the collective mounted switch he had hoped for.
I stress that this is rumour. I have no AS350 time so am unfamiliar with the exact hyd set up on this machine, but seem to recall other A-Star incidents of a similar nature due to poor ergonomics by Eurocopter.