Issue with last update of Plex Media Server Version 1.18.3.2156 in order to cast to Sonos

This morning, I can now cast to Sonos from Plex.tv web app, but only here. All other apps/PMP etc still generate error messages. And, the casting at Plex.tv only permits the playing of the first song as described in - Problem with casting to sonos and Sonos plays only one song on android as well as other topics on this issue. Thanks.