A setting change must be made within the android browser to enable playback of video in Youtube. Within the browser open the settings menu by tapping on the three dots in the top right corner. In the menu select Settings, then select Advanced. Now in the list on the right tap on Set User Agent. Change the setting for this to 'android 2.3 user agent'. Now close the browser and reopen it for changes to take effect. Videos should now play in Youtube.