MIDI oddities

[Voros]

There are number of MIDIs in Freedoom that have oddities, mainly just having emptyness.
What I mean is that when the tune in the MIDI ends, there's still 1-2 minutes left in the MIDI, which contains nothing more than silence.

Here are the ones I found:
-map22 (after 1:37)
-map27 (after 1:14)
-e1m7 (after 1:43)
-e1m8 (after 1:37)
-e1m9 (after 1:50)
-e2m2 (after 1:50)
-e2m3 (after 1:58)
-e2m8 (after 1:43)

map28 also has this problem, but I sent in a pull request to replace this with one of blueworrior's MIDI. In case you wish to know, its after 1:30.

I sent in a issue on this problem on GitHub. Is there anyway to trim MIDI files? Can you people do some in you free time?