I just bought SAMSUNG UA46F5000AM (in Indonesia) and I facing the same problem - if not worst.
The Media Play can't show the folder's content at all, the TV restarted/rebooted by itself.
The same HDD can be read smoothly with the old TV SAMSUNG LA40C530f1RXXD.
I already call the local Customer Care without any solution.
If you found the solution, would you share it?
Thank's in advance
PS.Sorry for my poor english
I bought a UE40F5000 recently and I play movies from an external USB HDD using the TV's built-in media player.
I found that the media player has a very slow response time. I mean when I push the "pause" button on the remote controller it still plays the video for several seconds before it is actually paused. For small videos (350 Mb) this "lag" time is around 6-8 seconds but for large HD movies it can be 25-30 seconds. The "stop" button works even slower. This is very annoying, the media player on my old TV (LE32C530) had much faster response. I don't think it's because of the HDD, I used the same one with the old TV and didn't experience anything like this.
Do you have any ideas how to fix this?