Closest thing to context I could find

https://www.supermanthroughtheages.com/a/Encyclopaedia/krypto.php

Edit: found the direct source : https://comicsarcheology.com/index.php/category/lois-lane/

A sentient piece of kryptonite is a superman papparazzi and accidently makes it so superman can only speak kryptonian. That… really seems to be the entire context.