Since you've switched to using HD trailers on some sites they freeze whilst downloading. The steam is way ahead of the point I'm watching so it's not running out of buffer. Most trailers are fully downloaded in 2-3 seconds. If I pause and then play them after they've fully downloaded it's fine. The streaming HD videos are fine in the members section, no need to pause or anything.
I'm on Firefox 28.
Anyone else find this?