We do know that it's best if you're using WIFI at home to ensure other devices on that WIFI aren't streaming, etc...
Also, another lesson learned about the software is it's best while watching not to resize your browser. Sometimes resizing will trigger the video to reload.
I watched a video after returning home late last night. I tried to skip ahead and had many issues with buffering. I then closed, reopened my browser. Started the video from the beginning, and let it run. When doing that, I no longer had issues (and I do experience issues on my home WIFI at times).
I hope this offers a little help.