Now I am using a freshly charged batterie, so this cannot be the problem. I read that the battery should not be beyond 50% but i am not sure if this was corresponding with the camera or ST16 - it was only an idea. I'm going crazy why it's no longer possible to flash todayDoesn't matter. I flashed a CGO3+ successfully with 12 volts powered steady grip. The camera uses 5 volts only, really with a big current consumption. It checks these 5 volts and doesn't initialize if they are low.