this is killing me. I'm having the exact same problem connecting from my Mac OS X 10.11.3 Xquartz 2.7.9_rc2 (xorg-server 1.17.4) X2Go Client v. 4.0.5.0 (Qt - 4.8.7) I've tried connecting to a CentOS 7 machine with either XFCE or MATE desktops and they both exhibit the same garbled keyboard behavior.