In Rapture Pro a sound is usually comprised of multiple elements, each of which loads separately from disk. If there are any problems during loading (such as incorrect path issues for multisamples), one or more of the elements may be silently loaded as an empty element. This is a misleading behavior that should be corrected in a future revision of Rapture Pro.
Any errors when loading a patch should be reported somehow in the Rapture Pro interface, via a MessageBox pop-up or some other obvious (and interrupting) mechanism. If there's a problem loading a sound I want to know very clearly what has happened, not have the instrument simply move forward playing whatever elements may have loaded, and letting me think that's the entire sound as intended by the designer of the patch.