Hello ,
yes the newer LibreElec is mostly very stable for the RK3328 Rock64 , however it still would struggle with the VC-1 content, slowing down and eventually reboot. dont know why, as it supposed to have to hardware decoding for such content. maybe the Bluray rips via makemkv is using a codec that is not so well supported?
now with the rp3 b+, the playback is smooth *with hardware keys for vc1, but again, have to disable wifi everytime manually if i load another OS, which is cumbersome.
hope to find another SBC that could work well with LibreElec sometime later.