VNC Session Chewing up CPU

I can connect to 10+ RDP sessions no problem at all, all are using the same configuration (32bit display, full color) etc. CPU usage for remotedesktopmanager.exe is pretty steady at 00% cpu usage while i'm not actively using it.
However, as soon as i connect to an embedded VNC session, remotedesktopmanager.exe is now using up over 50% of my CPU while it idles.
anyone else notice this ?


EW