I had the very same issue, and I managed to solve it by switching to phonon-backend-vlc instead of the default phonon-backend-gstreamer. This suggests that this is not a bug in minitube but much more likely in the phonon-backend-gstreamer package.
I had the very same issue, and I managed to solve it by switching to phonon-backend-vlc instead of the default phonon- backend- gstreamer. This suggests that this is not a bug in minitube but much more likely in the phonon- backend- gstreamer package.