It looks like KTLA has changed their stream this past week. I can no longer access the stream through Channels, but on their site and through their app there are no problems.
The server that the site pulls from seems to be slightly different than Channels is trying to access.
- Channels:
https://dcs-live.mp.lura.live/server/play/50ZGbepT8XD8SGRA/manifest.m3u8?encp=...
- KTLA:
https://dcs-live-uw1.mp.lura.live/server/play/50ZGbepT8XD8SGRA/rendition.m3u8?track=video-2&...