We have two young adult female cats and lately we have been noticing more of a smell coming from the litterbox and have realized it's because a lot of the time, they aren't covering their waste with the litter when they're done (even when it's just pee). I'm not sure if it's one of them or both, but it's only a recent thing. We always keep the box pretty clean, and I think they like their litter because it's a good brand that we've been using since before this started.

Has anyone else experienced this with their cats or know of a reason why they'd be doing this?

Thanks!