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CDJ 3000 Emergency Loop Fsil
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Yes, the whole file should be buffered, but it's possible there was a problem with the file or the connection in the buffer process. Without knowing a bit more about the setup (your network connections), what source you were playing from (USB connected directly to player, linked player), the filetype of the song being played, whether there are any errors with that file, if it happens every time you play it, etc.... there's a few places the error could occur.