The videos on the website stream through Vimeo, which automatically adjusts bandwidth based on what it perceives to be the internet connection between you and their video servers.
What I notice is that, similar to YouTube, occasionally I'll get the bandwidth lowered, and then after a few seconds it comes in full bandwidth. Unfortunately, with something like TAB, that is so detailed, any decrease in bandwidth is going to make it unreadable almost immediately.
My suggestion is to setup a loop. If there is a bit of a drop on the first pass, it should be cached and should not be and issue for the 2nd and subsequent passes.