PLEX app: Videos are stuck in buffering every minute.

Its become impossible for me to watch GB content on the PLEX app as every 1-2 mintues its stuck in buffering. The buffering lasts for about 10-15 seconds and then video continues again for about 1-2 minutes.

Anyone else having this issue?

I think its something to do with the switch to 1080p/60. If I use Plex on my PS3 with 1080p/60 videos, the video becomes a slide show, and on most other things the audio is a fraction out of sync. I get Plex to drop the video to 720p and it seems to play them fine.

This just started happening on any stream with which I use my Chromecast. Selecting the lower quality stream (which still looks pretty good), and then casting again solves the problem.