In a extended desktop youtube plays in full screen but In a wrong monitor

I have a strange problem that I decided to share it with you all. Well the problem is that I have a extended desktop and I have one screen as the computer monitor while the other one is the TV screen. Whenever I drag Firefox browser to the second screen i.e TV screen and if I start playing you tube videos in it in a full screen. Then it does not play in it. In fact it gets back to the normal monitor and starts playing in it. It happens only when I switch to the full screen and not in the normal view. Now why is this happening? If you all have any ideas then do let me know.

Well looking at your information I think it is a very little information that you have given here. I would like to have more information regarding the configuration that you have and which operating system that you are using? If you provide me with the details then I can help you more on that. So do get back to me with some more information and do specify more on the graphic card that you use for the system. Do reply as soon a s possible.

OK I am very sorry for that I will give you the necessary details regarding my configuration. I am a linux user and have a linux mint 10 64 bit operating system in my computer. Other configurations are here as follows
Graphics: Card-1 ATI Radeon HD 3200
Graphics Card-2 ATI RV620 LE [Radeon HD 3450]
X.Org 1.9.0
Res: 1920x1080@60.0hz, 1920x1080@59.9hz
GLX Renderer Mesa DRI R600 (RV620 95C5) 20090101 TCL DRI2 GLX Version 2.1 Mesa 7.9-devel
I hope you have got the necessary information on my system. Now I think you can give me the necessary details on it.

OK you are using the linux mint 10 64 bit operating system .According to me the linux mint 10 comes with the mint-flashplugin as a default plug in. So do have a check for that particular plug in. Also try reinstalling the adobe flash that you are using. In case you don’t have the particular plug in your system then ensure that you install the particular plug in your system. So that there will be no problem while viewing videos. So do the following changes and it will definitely help you.

I would advise you to disable the hardware acceleration that you use it while viewing the you tube videos. What you have to do is when you are viewing the you tube video
1) Right click on the video that you are viewing and click on the settings.
2) You will get a flash pop up and if enable hardware acceleration option is checked then do uncheck it and click on close.
3) After doing that you have to restart the browser and check again if the video is playing in the full screen.
It will definitely get played. So do try with this method also and do let me know if it works or not.

Hey thanks a lot everyone for the solutions that you have provided. Well I had a plugin named flashplugin-nonfree which was there In the package manager. So what I did was removed it and I replaced it with the adobe-flashplugin. After replacing it with the particular plug in I was able to watch the videos properly in the TV screen properly and also In the full screen mode. It worked perfectly well and your solutions have really solved my problem. Thanks for your efforts.