In my case freezes disappeared when I removed the gnome ppa (https://launchpad.net/~gnome3-team/+archive/gnome3).
Having the gnome-ppa installed produced freezes not only in gnome-shell, but also in Unity.
In my case freezes disappeared when I removed the gnome ppa (https:/ /launchpad. net/~gnome3- team/+archive/ gnome3).
Having the gnome-ppa installed produced freezes not only in gnome-shell, but also in Unity.