mplayer播放时有声音，但屏幕一片蓝色，为什么？

maxofmin

环境：gentoo1.4
kernel 2.6.0test9
显卡是intel815e，
我按照精华区的文章，已经开启了显卡的3d加速(glxinfo | grep rendrering显示yes)，xvinfo显示如下
X-Video Extension version 2.2
screen #0
  Adaptor #0: "I810 Video Overlay"
    number of ports: 1
    port base: 69
    operations supported: PutImage
    supported visuals:
      depth 16, visualID 0x23
      depth 16, visualID 0x24
      depth 16, visualID 0x25
      depth 16, visualID 0x26
      depth 16, visualID 0x27
      depth 16, visualID 0x28
      depth 16, visualID 0x29
      depth 16, visualID 0x2a
    number of attributes: 3
      "XV_COLORKEY" (range 0 to 16777215)
              client settable attribute
              client gettable attribute (current value is 2110)
      "XV_BRIGHTNESS" (range -128 to 127)
              client settable attribute
              client gettable attribute (current value is 0)
      "XV_CONTRAST" (range 0 to 255)
              client settable attribute
              client gettable attribute (current value is 64)
    maximum XvImage size: 1440 x 1080
    Number of image formats: 4
      id: 0x32595559 (YUY2)
        guid: 59555932-0000-0010-8000-00aa00389b71
        bits per pixel: 16
        number of planes: 1
        type: YUV (packed)
      id: 0x32315659 (YV12)
        guid: 59563132-0000-0010-8000-00aa00389b71
        bits per pixel: 12
        number of planes: 3
        type: YUV (planar)
      id: 0x30323449 (I420)
        guid: 49343230-0000-0010-8000-00aa00389b71
        bits per pixel: 12
        number of planes: 3
        type: YUV (planar)
      id: 0x59565955 (UYVY)
        guid: 55595659-0000-0010-8000-00aa00389b71
        bits per pixel: 16
        number of planes: 1
        type: YUV (packed)
编译mplayer时已经打开了xv，但是一使用mplayer就只有声音，屏幕一片蓝色，请问高手们知道怎么解决这个问题吗？