Seguramente no haces mal nada, lo que pasa es que el Dune, como no soporta realmente HDR, no puede forzar el HDR en tu TV. Tienes que forzarlo manualmente tú. Del changelog del último firmware:
- Automatic HDR conversion can be enabled/disabled by the new setting "Setup / Video / Advanced / BT.202/HDR conversion" (enabled by default).
When using a TV with HDR support, it is recommended to disable HDR conversion on the player and force HDR mode on the TV.
- HDR conversion can also be quickly toggled during playback using RC button "MODE" (on Duo 4K) or "KEYBRD" (on Solo 4K and Solo Lite).