[Gee11]

I would say it's an issue with the stream itself, or possibly with access price on your server:

Code:

22:16:53.197 T:5924 NOTICE: AddOnLog: MediaPortal PVR Client: Cannot access 'X:\\live11-0.ts.tsbuffer' directly. Assuming multiseat mode. Need to translate to UNC filename.
22:16:53.197 T:5924 NOTICE: AddOnLog: MediaPortal PVR Client: Translate path X:\\live11-0.ts.tsbuffer -> smb://xxxx:xxxxxx@SERVER/Timeshift/live11-0.ts.tsbuffer

22:16:53.514 T:5924 WARNING: CVideoPlayer::OpenStream - Unsupported stream 0. Stream disabled.

Also you've got Kodi running with admin rights, which is neither required nor recommended.

The log also contains your server login credentials, so may need redacting (it also doesn't have debug log enabled). 

But it cant be an issue with the tv stream. It works with Kodi 17 mepo tv plugin. And movies with mutch higher bitrate plays fine also. I think its the buffering on tv streams that changed in Kodi 18. Maybe Marcel Grootis can help me here