If you’re on Linux you probably miss the Gstreamer Phonon backend or the GStreamer codecs (or both). Install phonon-backend-gstreamer, gstreamer-ffmpeg and gstreamer-plugins-bad. If the problem persists, try to run this command
sudo ln -s /usr/lib/kde4/plugins/phonon_backend /usr/lib/qt4/plugins/phonon_backend
On the Mac someone reported problems with very old G4 machines. No solution for that.
You probably have an nVidia video card. If yes, this is a known problem of the nVidia driver, Minitube has nothing to do with it. This problem should be fixed in driver version 185.
You probably have an old Qt version. Minitube requires 4.5 or better. You can check by running Minitube from command line. It should give something like:
./minitube: symbol lookup error: ./minitube: undefined symbol: _ZN18QNetworkProxyQueryC1ERK4QUrlNS_9QueryTypeE
Hey, you didn’t try Minitube, did you? Anyway, by that reasoning you could also use youtube-dl and mplayer… The whole point of Minitube is to create a sophisticated and functional User Interface that lets you enjoy YouTube content as if you were watching TV (or listening to a radio). Totem, as a generic media player, will never overlap with Minitube.
You probably downloaded the 32bit binaries. Find a package for your distribution or get ready to compile Minitube by yourself (It’s fairly easy, by the way…).
I beg to differ. The author’s primary desktop environment is GNOME, not KDE. Qt integration problems in GNOME are a thing of the past. With recent Qt versions the native GTK+ style is used. You’d be hard-pressed to tell that Minitube is not a pure GTK+ application. So please, stop the toolkit wars and enjoy Minitube.
There’s no option, Minitube uses the system locale. On Linux, you can always workaround this by setting locale variables before running minitube. Something like:
LANG=it_IT.UTF-8 && ./minitube
On the Mac change the language from the system settings.