Since a couple of days, I'm having the same problem on my Samsung Galaxy TAB (GT-P1000)
OS : Android 2.3.6 (Gingerbread)
- When I want to play a video, I get a black screen with a small white
line at the bottom.
- When I switch to Desktop mode instead of Mobile, then it's working
(but it's slower then).
- I think that the difference between desktop and mobile, is that for
the mobile version, youtube is using RTSP (together with .3gp files) and for
the desktop version, they are probably using HTTP & Flash.
- I have tried it with the stock browser, with Dolphin HD and Mini and
with Opera Mini, all having the same result.
- I have also tried it on my Samsung Galaxy Mini with Android Froyo and
on a Nokia E72 and on both of them it's working fine.
- When I try to play a video on my Laptop, through m.youtube.com, then
it's also not working.