js掉后后台得到flv播放路径，并添加到FLASH路径中，有时显示有时候不显示

我用js调用后台并得到视频播放地址，然后将地址用通过js填入调用FLASH的HTML中，但有时候会显示有时候不显示 什么情况！代码：var flashHtml = "<object classid='clsid:D27CDB6E-AE6D-11cf-96B8-444553540000' codebase='http://download.macromedia.com/pub/shockwave/cabs/flash/swflash.cab#version=7,0,19,0' width='433' height='272'><param name='movie' value='http://localhost:9966/flash/CuPlayerMiniV20_Black_S.swf?CuPlayerFile=" + json[0].videoUrl + "&CuPlayerImage=../images/flashChangfa2.jpg&allowfullscreen=true&CuPlayerShowImage=true&CuPlayerWidth='476'&CuPlayerHeight='300'&CuPlayerAutoPlay=false&CuPlayerShowControl=true&CuPlayerAutoHideControl=false&CuPlayerAutoHideTime=6&CuPlayerVolume=80' /><param name='quality' value='high' /><param name='allowfullscreen' value='true' /><embed src='../flash/CuPlayerMiniV20_Black_S.swf?CuPlayerFile=" + json[0].videoUrl + "&CuPlayerImage=../images/flashChangfa2.jpg&CuPlayerWidth=476&CuPlayerHeight=300&CuPlayerAutoPlay=false&CuPlayerShowControl=true&CuPlayerAutoHideControl=false&CuPlayerAutoHideTime=6&CuPlayerVolume=80' quality='high' allowfullscreen='true' pluginspage='http://www.macromedia.com/go/getflashplayer' type='application/x-shockwave-flash' width='433' height='272'></embed></object>";这是用js拼出的HTML 红色为后台去出的路径