Video playback help needed

Hi,

I have been having problems when I watch online videos. The video will playback fine for a few mins then it will freeze for a second and then continue playing but the video counter changes to NaN:NaN (see attached image) I am then unable to skip through the video or pause/stop the video unless I close the webpage. The problem appears to be solved if i disable on of the addon's shockwave flash object but if I disable this addon I then can't maximise the video to full screen. Does anyone have any idea what might be causing this and how to fix it.

I have tried reinstalling this addon but this didn't help I have also tried reinstalling flash player.

My computer is an Emachines E440 P320 AMD Athion II x2 With ATI Mobility Radeon HD 4250 - all drivers are up to date.

Thanks in advance

Floyd

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