All peaks are rebuilt upon new media insertion

Hi guys

Im working on a huge, one hour project with a ton of items (well, not that much, around 150), and each time I insert a new media, Reaper rebuilds all of the peaks.
Is there a way to get rid of this ? I dont wanna uncheck the "generate peak caches on import" option course, I just want reaper to build the new item's peak, not rebuild the whole stuff (whats the point ?)

Thanks

All peaks are rebuilt upon new media insertion