Looks like there are a bunch of Famitracker modules (.ftm files) that are converted to MIDI but should actually be converted to NSF like any other NES song.
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Over the years I received numerous requests from people that wanted more: more music, more features, more playable formats, you name it.
Eventually I began working on a complete rewrite of the app (this time for real), and, realizing that each year another chiptune or MIDI website went offline, I decided to start archiving them for preservation.
Today, 10 years after the first release, I think it's finally time for the new, nicer version to hit the shelves. It's now called Pixeltune and yes, now you can actually turn down the volume. :)
Hope you like it!
This was all done before I ported Furnace Tracker (that also supports the .ftm format) so I might just use Furnace for playing them. I have to check whether it can play the newer .ftm versions.