The latest FW and Mol1 should be installed on your device.
Try with this steps:
1. Home menu-> Cog wheel -> Android -> Apps -> Mytvonline -> delete cache and data. Try again with add and delete favourite channel.
2. Delete your current Portal or Playlist and add again new one.
3. If all not helps, factory reset and fresh setup.
I'll hope this will work. Thank you!
But since I once ruined the bios update of a computer I lost quit some faith in myself doing such things. I will ask the man who installed my Formuler if he wants to do this for me.
I will give feedback here!