[Lists] Displayed stream quality not reliable

In the series view, a small quality indicator is shown (720p/1080p) on the bottom right. How is this quality determined?

I am running this plugin on two different devices and each device shows its own quality indicator for the same show. One device shows 720p and the other 1080p. The device that displays 720p will not stream above 640x480 while the one that displays 1080p streams at 1920x1080. The first device has no problem playing other shows that display the 1080p indicator.