I was stating the opposite (sorry - ambiguous wording in my post above) I think "No one" who purchased Jammit tracks from Jammit, "owns any" right to use them as of the time Jammit ceased to be - of course these tracks are not public domain. Some seem to assume they can hand Crammit 25$ and legitmately continue using the tracks they purchased via Jammit hmmm.
I don't have backups of the 1-200 tracks I purchased from Jammit, but if I did, and recovered them, I'm not at all sure I'd be legally using them within a different player than the original Jammit player (or even at all, in any context, for that matter)