Muse is a very solid piece of work.
MuseTracker is the only PCM baste NES tracker that has compatibility with a tun of NSF players, VirtuaNSF, VirtuaNES, NSFLive, SlickNSF (however NSFs play a little slower than their intended refresh rate) NEZplay Etc, and it does a pretty good job, the NSF exporter is vary stable and handles the code vary well, and it seems to do a much better job than in DefleMask.
DefleMask's NSFs are fully compatible with the NES; so, in fact, those NSF players that you mention are not fully accurate, rather than DefleMask being not compatible. The technic used by DefleMask to do 7bit samples is discussed here @ nesdev.
I recommend only NSFPlay by rainwarrior, it was updated to support DefleMask's NSF a year ago.
Btw, DefleMask has the advantage of multi sampling rates @ 7bit samples (4000hz, 8000hz, 11025hz, 16000hz, 22050hz, 32000hz!!!), in Muse you are forced to use 8000hz. You can get better samples in the NES than 8000hz as DefleMask proved.
Liek this WOW