On 18 May 2011 during the Endeavour's arrival at the International Space station NASA had stop the live stream after the three UFOs appeared in the Endeavour's background?.
Interestingly ground Control had ordered the ISS crew 'Endeavour please pause the playback' which raises a lot of questions and emphasizes the need for more independent (from government control) space monitoring.
Its a very unusual call as if the objects were just space junk, NASA would have just ignored them but they essentially stopped the live stream, while the objects pass the Endeavour's background.