Bingowings said:

It is weird how they choose which clips to munch.

Its because they compare your clip with a copy of the film/music you used, that they have, and if there is a match, the take it down/block it.

However there are fixes for this:

Video:
#1 You can flip/mirror the video, and it should go through
#2 You can use the dispute process (though it may end badly)

Audio/Music:
#1 Speed up the audio/music 1 or 3 percent in audacity.
#2 You can use the dispute process (though it may end badly)