I have used the buffer size and made sure all used apps etc are disabled but so annoying has anyone a solution for this please
Are you using Kontakt 7.6.1?
If so, reverting to Kontakt 7.6 may fix.
mac:
Kontakt_7_760_Mac.dmg
https://drive.google.com/file/d/1vYrco-bfZXK18VWVoEoWLS6HZBd2-oPH/view?usp=drive_link
Win:
Kontakt_7_760_PC.zip
https://drive.google.com/file/d/1GjQtdHYtc-jElijJQOYRkT-eri9NZskH/view?usp=drive_link
Ref. : https://community.native-instruments.com/discussion/17691/kontakt-7-6-1-update-causes-cpu-spikes-crashes