Voted in the poll but the solution (at least to me) is fairly simple. As some mentioned, do it like what other filehost does and give a major percentage of the money generated from the leechers file to the original owner. I'm sure no uploader would complain since the leechers are indirectly giving the original owners extra money.
The problem with leechers spamming forums with the same stuff is because internal RU is free and quick. My suggestion is to use internal RU as a feature to be used only with the playsonic credits as some sort of bandwith quota. Example : 6Gb of internal RU bandwidth for 300 playsonic credits or so.
Leechers would eventually stop abusing the feature since they have to spend credits on it and only get a small percentage of the sale/download from the leeched files. Of course, all of this takes time/resources to create such a system and Filesonic could take the easy way out which is what they are doing currently; blocking internal RU

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