Have you tried different HDMI inputs on the TV? Sometimes it's the TV that has to be "rebooted". Unplug the power for several seconds. Simply turning it off and on doesn't really accomplish anything.
For the language issue, while the video is playing press * on your remote and check under the Accessibility options for a different audio track. Depending on the app you're using, it may have language options that can be selected before you start the video.
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