First of all - I have had this problem with other articulated buses before, but only in very low fps (1-5) situations. The other Hamburg buses have this problem - but to a much lesser extent. Addon articulated vehicles - such as the Citaro G by Alterr - do not have this problem at all.
Basically, when I spawn a C2, no matter where I spawn it, it will jump around like crazy. I can sometimes get it into drive, and be able to drive it off, and it smooths down a bit. It will the jump around again after driving for about 30 seconds. It will calm down, and then repeat. Can someone explain what is causing it?