AudioSource only updates about 25 times per second, meaning that even at
30 fps some adjacent frames would be calculated as having exact same
timestamps and render duplicated colors. At 100+ fps more than 2/3 of
the frames would be duplicates.
As a drive-by change, split complex logic of BeatTimeState into smaller
classes. Most of the time the state needs to maintain some boolean flag
which it flips once and stays that way, like HasStarted, IsLooping.
ivan tkachenko