Diggz Team

If you want to quickly check if a source is buffering you might use CTRL + Shift + O (or map this to a key on your android remote using Keymap Editor addon).
After the word forward, it will show how many MBs the source has buffered, a cache percentage, and milliseconds of movie/episode remaining.
This can be done while playing the movie/episode or you may pause it. If it stays 0 or it moves really slow, you might have to get another source.

Buffering on Movies, TV or Sports.

Glossary:

aq = Audio queue saturation
Kb/s = Current audio bitrate (reported by player)
att = Attenuation / gain added by player
vq = Video queue saturation
Mb/s = Current video bitrate (reported by player)
fr = Source framerate
drop = Number of dropped frames
skip = Number of skipped frames
pc = Pullup correction pattern length
a/v = Audio/video sync difference (real time)
forward = Size of cached data and % of cache utilized
VsyncOff = Indicates the offset between the vertical sync signal of the display and the timestamps of the video frames

https://kodi.wiki/view/Video_playback#Player_Debug_Info
https://kodi.wiki/view/Codecinfo