Quality control I imagine is always a difficult issue. Even when you control the binaries, software isn't always going to act the same on all systems. However the problem is exasperated when all that is released is a tarball, like we do with Amarok. For instance, we decided to remove the gstreamer 0.10 engine. It has several open bugs and its maintainer (Paul) would be the first to say its not ready yet.
So we removed it from the build system Makefile.am and commented it out of the configure.in.in. But apparently despite our best effort to release a quality project,
we recently discovered that Fedora went behind our back and re-enabled the gstreamer 0.10 engine for their amd64 builds. Remember, this engine has
never been part of a stable build. And then our users come to us wondering why stuff doesn't work... they generally don't like being told its because their distro is silly. :/
So while fiddling with my server a couple of days ago I noticed that metadata now works correctly when adding DAAP songs to the playlist. I think I did know that Martin was going to work on this (the problem was applicable to iPods as well) but I hadn't notice that he had actually finished.