Have tested a lot of Openpli versions but cant get it work. Sound/picture does not sync. How can I solve the issue?

I try to install Openpli on my dreambox one.

I first have to flash the box with latest NewNigma 2. Then flash the Openpli image?

And do I have to uncheck "backup and restore settings" both boxes before any of the flashing steps?

This steps still doesnt get working pic/sound