Lmms has been out of date for quite a while. It's been flagged out of date on June 13th. I emailed the maintainer Mateusz Herych telling him that only the pkgver and checksums have to be updated. He answered, that he's too busy in real life to take care of it.
I don't know if this applies to many other packages and is "normal" for the community repo, but I think it would be better to find a new maintainer for lmms, since it's far behind (0.4.10 in the repos vs. 0.4.12 upstream).
If this is considered rude, please forgive me!