I was playing back The Incredible Hulk on BD just fine until about chapter 16 when I decided to rewatch a chapter, so I skipped back, but then video studdered and the unit locked up.
After several reboots and power cycles, it seems I can play from the beginning just fine, but I can fast forward, rewind, or chapter skip without the unit locking up.
No special features are turned on.
Could be down to the individual disc (or problematic hardware). At an earlier chapter, I did some pausing, rewinding and fast forwarding on repeated occasions without a hitch.