Any details on the power supply driving the hub? My recollection is that you should
plan on a minimum of 1A @5V for each BiFury when running at it's normal low clock
speed. I think it can go as high as 1.8A.

A few other debugging thoughts:

- How long will it run with just 1 BiFury plugged in?

- How long with two?

- How long with three?

If shrinking the number of BiFurie's makes things better, think power for the hub.