Can you make sure your sound system is set to OpenAL?
Yes the sound system was set to OpenAL. But I found my fault. I haven’t connected a loudspeaker to the test PC, so Windows 7 did not initialized the audio driver.
Windows 7 64 Bit:
Blender 2.57 32 bit OpenAL --> working good
Blender 2.57a 32 bit OpenAL --> working good
Blender 2.57b 32 bit OpenAL --> working good
Blender 2.57 32 bit SDL --> working but the video is jerking
Blender 2.57a 32 bit SDL --> working but the video is jerking
Blender 2.57b 32 bit SDL --> working but the video is jerking
Blender 2.57 64 bit --> video freeze and after 4.2 second
Blender 2.57b 64 bit --> video freeze and after 4.2 second
I have tested Blender 2.57(b) 64 bit it with the video texture example form the tutorialsforblnder web site but with the same result.
So I think it must be a bug in Blender 2.57(b) 64 bit oder in the video texture module. http://www.tutorialsforblender3d.com/Game_Engine/VideoTexture/VideoTexture_Movie_1.html