[X2Go-User] 25 user logon problem

Hello everyone;

I have set up a x2go terminal-server on ubuntu 12.04 in our school. There are 25 thinclients (wyse with windows7 embedded) in a classroom. The thinclients start with an openbox-session. So far it works fine, but there is a little problem:

If more than 2 or 3 clients log on at exactly the same time, some of them stop at the black screen before the gray X2Go Logo appears. There is no error message. With a little timeshift of 2 or 3 seconds between the logons, there are no problems.

Can anyone get a little help to solve this?

Regards, Th.Hanschke