I can't quite put my finger on when, but a while ago - i think post-update - i started having an issue remote controlling/casting to other PHT devices.
I run Plex Media Server (latest stable) on a NUC device running Win 10 Pro..
I run PHT on the same device connected to my TV, also have PHT on an iMac in another room.
Whenever I cast to PHT now (i just want to remote control), I get the movie/tv show start to play on the PHT device and it will keep playing through, but i'm stuck with a spinning wheel in the iOS app (iphone/ipad, latest version) and it can't track duration, play/pause doesn't work and i can't rev/fwd.. i can choose a chapter and do it that way..
If i do the casting via web (http://server:32400/web) it works, and i can see the progress bar, so it seems only to be on iOS devices. I've updated PMS and PHT to latest versions and it hasn't fixed yet..
Anyone else having this problem?