The Orange Pi range are based on Allwinner SoCs which have poor Open Source drivers for the VPU (the bit of the SoC that actually plays video). There have been a number of attempts to improve this, and all so far have failed. All winner don't really seem to be that interested in working with Kodi devs to sort this, and apparently have a patchy history with open source licence compliance.
http://forum.kodi.tv/showthread.php?tid=238060
"Currently, the combination of the kernel driver and VA-API backend supports MPEG2 and MPEG4 decoding only. There is for the moment no support for encoding, and no support for H264, though we believe support for both aspects can be added within the architecture of the existing driver and VA-API backend."
