Bug with sdl2 render in win7

when i play an video with sdl2, it played the video normally in serveral
seconds. But then the video freeze and block forever.
I debug in the SDL2 function, i found that when D3D_RenderPresent calling
IDirect3DDevice9_Present, sdl2 block and never return back.
I have installed the directX 9 Sdk(June 2010)