[houser]

Just returning to mention for others looking for a solution for this, that it started working after some excellent advice from here:
https://getsatisfaction.com/irule/topics...n-delivery
The trick with iRule for at least me was to drop the encoding and use a network gateway rather than http.
Along with some cleverly doctored fixes in that thread it works great. FWIW, YMMV
Good luck.

What do you mean by "drop the encoding"?  I have my gateway reconnected to Kodi via Network Gateway and I get a green sync in the app so I believe that part is working... my formatting on the command just must be off but I can't figure it out.

Thanks. 

Hi John,

I meant URL encoded or not. Example below of the same command encoded and not that works here FWIW:

Play/pause toggle Kodi 18.xx non encoded:
jsonrpc?request={"jsonrpc":"2.0","method":"Player.PlayPause","params":{"playerid":1},"id":1}

Play/pause toggle Kodi 17.xx encoded:
jsonrpc?request=%7B%22jsonrpc%22%3A%222.0%22%2C%22method%22%3A%22Player.PlayPause%22%2C%22params%22%3A%7B%22playerid%22%3A1%7D%2C%22id%22%3A1%7D