Dear Admin,
Thank you for your help in the beginning. I do not use media player for the first time. I have used many brands and model media players before. I only used models like PRIME 3D, DUO, TV 301, BASE 3D that belong to the Dune brand. I used the Himedia Q10 Pro. I just sold himedia q10 pro media player to get the Dune HD Pro 4k. As you said, the fact that very few users have this problem does not mean that the product will not be faulty. I reach this result from here.

I have a qnap ts-869 pro. I use the Dune HD Pro 4k with qnap. When I started x265 video 1080p or 4k dune give black screen but sometimes give only audio. This problem has when I played only x265 video. x264 video work fine and picture and audio quality perfect.It turns off and restarts itself as it does not display on some x265 videos.When I tested Jellyfish videos, I did not see a problem with only x264 format ones.However, the problem with the black screen continued in the x265 and 10bit ones.When I selected the player as an external player, some x265 videos came out.But most of the problems continued in the same way.I think that my device may be defective.Because there are not many problems with this kind of user.

Everyone wish good forums.
Thank you in advance for your help.