While having changed absolutely nothing to my setup, my Garritan CFX Grand sound library recently started to induce speaker overflowing cracking sounds and/or suddenly stop processing the sounds altogether.

Observations:

1. Immediately after startup of the the library and choosing a piano sound my total RAM is around 50%, over the course of some time using it, it goes up to around 60% or higher. The only application growing bigger being the Garritan library. How come?!
2. Today when playing from my Kawai VPC 1 midi controller, the library crashed twice stopping to generate sounds altogether showing the following message however (see screenshot):

I have checked the preferences and for years they have always remained the same (see screenshot):

Changing the Audio Device Driver does not help: there is no sound.
Changing the Sample rate also makes no sense/difference, besides the 44100 Hz (lowest) has been working for years already.

Does anybody have a clue as to what is going on here and how to fix it?

Many thanks,

Waldemar