We bought a Blu-ray player a few weeks ago, and it had been working fine until we did a firmware upgrade / plugged it into the network.. when it became unresponsive. Did some digging and found it behaves terribly when it’s connected via HDMI to a non-Samsung TV with CEC-Link (aka vieralink, anynet, etc). Turned that off and it works fine.
Hope this helps someone on the internets.
(also *cough* we crossflashed it to the Singapore firmware which lets you set it into region-free for DVD :)