What do I do here as I hear the instrument ( I do not know if this happens with ALL instruments)
Stumbling upon this thread. This kind of graphic issue can usually solved by opening Kontakt in standalone and choosing a compatible audio driver, SoreAudio for Mac and ASIO for PC.
Did you try clicking on the '!' button to refresh the library?
Did you install using Native Access 1 or the latest version?
I had similar issues when I first installed Kontakt using Native Access 1 but using the current version 2 fixed it
Im using NI 3.81
Re Instaled Kontakt
Reinstalled the Kontakt instruments as well, same.