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Seems LiveLeak.com site was updated or changed API (now I can't see "embed" button).
All added before videos are available in JomSocial and can be played.
But now it's impossible to add new videos.
Can you please contact with LiveLeak.com?
Link looks like
But Relevant embed codes has another ID now:
<iframe width="640" height="360" src="//www.liveleak.com/e/5f9c9be0fd63" frameborder="0" allowfullscreen></iframe>