Hey! chewitt, I have tested the branch https://github.com/chewitt/LibreELEC.tv/commits/rockchip rebased on top of the master branch (commit 4757d991927641ece8d1fbc6c054244c2a366405) and it works well on RK3399 (Radxa rock 4) 
Hey! chewitt, I have tested the branch https://github.com/chewitt/LibreELEC.tv/commits/rockchip rebased on top of the master branch (commit 4757d991927641ece8d1fbc6c054244c2a366405) and it works well on RK3399 (Radxa rock 4)