Broken Spokes

I have a couple of spokes break at the rim end of my factory built deep v wheels rear wheel. What might be the cause? is it worth getting it rebuilt with high quality DT swiss spokes etc?

Is it the spoke breaking or the nipple? And yes, yes it is worth upgrading to DT/Sapim spokes. CN spokes (and other bad spokes) just don’t last. Wheels also like nice high spoke tension, and not enough spoke tension is a really common form of wheel failure.

Yes both times they’ve broken at the nipple, thanks for the advice,