XRDP Strange keyboard behaviour

I recently installed 11.3 (fresh install). Before I was using 10.1 and Xrdp without any problems. Now when I connect from my Dell-Laptop (running windows 7), then during login screen all keyboard characters work. After Login, not all keys work anymore. E.g. key 2 and 3 or 6 and 7 don’t work. There are many more.

What is strange, that it worked before on 10.1 using same configuration.

From my IPAD (using iTAP) have have these problem not.

I tried alreadyg conf-editor and disabled /apps(gnome_settings/daemon/plugins/keyboard - but without any change in behaviour.

Any ideas what the problem could be?

Thanks