That indicate to me, that you are on an oldi'ish lmms release, ao you have midi note import in that project.
Do you get any error message show, or is it 'just' a freeze?
What you should do is:
backup your own stuff, then uninstall lmms completely, including the config dot-file:
Read:
http://lmms.io/wiki/index.php?title=LMM ... h_Settings
DL and install 1.2.0 RC6 with the orange buttons on dl-site:
https://github.com/LMMS/lmms/releases/
If you still have issues, i will maby be able to 'fix' your project, but if its a mmpz-file, it does need to have flawless data. If its a mmp-file, it will just fine.
But try the above things first
Besides that, since you are new in Forum
Welcome Get a david
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