Hello,
I have the following problem with my DM8000:
First I flashed the OpenATV image. I connected the dreambox via Wifi to the network. As I switched to a stream the box freezes. Also all network connections were broken. The same happens if you try to upload a huge amount of data (e.g. Picons) to the dreambox.
This behaviour is only reproducible when the dreambox is connected via wifi. If the box is connected over a cable, there is no problem.
Yesterday I flashed a OpenPLI 4.0. And I could see the same behaviour as with the OpenATV image.
To ensure that it is not a hardware problem, I flashed also an original DMM image and also a Merlin image. With this two images I had not that kind of behaviour.
In the OpenATV forum I find (at least) another person you has the same behaviour as described.
Are we doing something wrong? Has anybody a suggestion how to solve it (except "connect the box via cable" 
)? Could somebody look to it please?