[Kaido]

Can you explain how did you solve the problems? 

Here

Sometimes it happens to me as well, it looks like the .../userdata/addon_data/plugin.googledrive/accounts.cfg file gets corrupted or something. So either delete the file all together OR delete your Google account from the plugin - either way you will have to add it back it. It will work right after you do it. 

Thanks, but I was asking Kaido, who had problems playing 4k stuff

Sadly, I still have problems of buffering 4k so my bad. Idk if I need install “X 18.0 Kodi version” or Idk, its actually working better than kodi 18.5 but still getting buffer each 10 mins or just randomly.