Hello, same problem here. Afters hours (3-4H, random) , session becomes slow, clic very long to respond. No network problem, no load or CPU high on server, everything is normal on server. I was unable to reproduce at any time. and i wad unable to guess what KDE4 app is problem. Application that are used : Dolphin, Open Office Calc, sometimes Firefox Closing session et restart it is OK. I can make some tests or look for logs if you want.. Thanks Package: x2goserver Version: 4.1.0.0-0~1303~ubuntu14.04.1 The client machine's OS: Window 7 or Linux Debian Jessie The client machine's version of X2GoClient: 4.0.2.1 Any relevant session settings in X2GoClient: KDE 4.13 session The server's OS: Ubuntu 14.04 64-bit The server's version of the x2goserver package: 4.1.0.0-0~1303 The server's version of the x2goserver-xsession package (included in server package) : 4.1.0.0-0~1303~ubuntu14.04.1 The server's version of the nx-libs package: 3.5.0.33-0~671~ubuntu14.04.1