1 - Go to http://www.adobe.com/shockwave/download/alternates/ and download deb file (install_flash_player_10_linux.deb).
2 - Uninstall previous players from synaptic package manager like gnash, libswfdec..., or any other flash related package
3 - Install deb file with sudo dpkg install_flash_player_10_linux.
This worked for me...