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Wednesday 7 March 2018 at 16:03
There is a factory reset in the service menu that will reset the high scores and audits for you. I am embarrassed to admit, I think I just did not think about adding a high score reset option to the service menu... oops.. I will get it in the next release.
--Scott
Source: http://pinside.com/pinball/forum/topic/total-nuclear-annihilation-cluball-welcome/page/36#post-4267520