There are 2 solutions:
1. Deactivate the UHD Color function on the HDMI Input of the player on the TV.
2. Go to the settings of the Zappiti player, then choose "Developer Options" and select:
- 10-bit on "Deep color mode"
- RGB 4:4:4 on "color space mode"
The image and the sound should no longer disappear on your UHD TV.
Be careful! On some TVs or front projectors, RGB mode requieres specific settings on the TV/projector due the different dynamic range used in RGB. This option can be named "HDMI Full Range" (depends of brands). In addition, in inverse, some TVs, projectors or AV Receivers cannot support well the RGB mode. In this case, please try the Y'CbCr 4:4:4 or 4:2:2. This kind of settings can fix audio or video drop or lag issue.