Seems like the vocals are clipping in several places. Wondering if they were recorded hot? Like TripleM, I'm hearing the crispies. Check to see if the vocals clip without any inserts active, because what may happen is the vocals go hot into a plugin where they are then compressed and don't appear to clip (VISUALLY). But by then, it is too late.
Digital audio is all about the zeroes and ones, but you're limited by the number of bits you have left in a hot signal. When you're working with the dbFS scale and you only have -3db of headroom before you hit the ceiling, you could inadvertently clip inside a plugin before the signal comes back out of it. Maybe your EQ or compressor boosts the signal slightly internally.
This would be something you could never know; the signal could hit the dbFS ceiling internally and visually you would never see this because the output from the plugin goes into the next insert in the chain. By the time it hits the fader, the level could LOOK ok... but the clipping has already happened inside the insert plugins. (Just something to think about).
This is why lately I try to track vocs no louder than about -18 to -12 dbFS... the noise floor is incredibly low on most good audio interfaces these days, so there's not as much reason to track hot any more.
Back to your mix.... listening objectively, the two things (other than the crispy vocs) that stand out in a bad way are the drum sound and the low-end definition (roundness) on the bass guitar.
Drum sound overall seems harsh and a bit too boosted in the highs, and IMO it makes the drums sound wrong for this tune. Maybe it's the reverb on them that sounds way too bright.
The bass guitar sounds a bit wooly in the low mids
