Hmm... my trusty sliderule tells me that at 2.2mbps 65MB can buffer almost 4 minutes of "stuff". 2.2mbps = 275KBs, divided into 64MB = 232 seconds. Even if it's only half available for buffering, a 2 minute interruption in your streaming just shouldn't ever happen.
The 2.2 number is only an average though.
If there's a particularly motion intensive scene, that number can jump to 6mbps for the duration of that scene, bringing the buffered time down to ~85 seconds. So even if your connection doesn't completely die, if it just experiences an extended slowdown for a couple of minutes it would be enough to cause a rebuffer.