As can be seen from the webpage archives, the popular french musician and conductor Frédéric Chaslinpurged every track except one of his SoundCloud repository early this year.
Some of the tracks are covers of classic musicians like Beethoven, which were played by an orchestra that was directed by him. He uploaded them in early 2013. According to description, these played on radio! His exact iteration of some of the tracks like the fifth symphony currently are nowhere to be found after having been on air for nine years (over 3.000 days) with over 700,000 plays and over 15,000 times favourited.
It used to be the first result on SoundCloud for Beethoven's fifth symphony (archive), meaning it was the most popular iteration.
Spontaneous takedown by uploader is a risk not to be underestimated to any online media. Statistically, it appears to be very high up in the "leading causes of fatality" for web media.