Try enabling the limiter in Wavelet. Wavelet doesn't have a manual pre-amp you can set to negative, so I think you deal with this using the limiter instead. It sounds like you might be getting clipping if you have a lot of positive boosts.
Alternately, you can try to rejig your AutoEQ output so it cuts more than it boosts; if using Squig.link to generate it you can do this by first normalizing the headphone and target so the headphone is all or mostly over the target. When AutoEQing then, it will cut rather than boost and ideally you'll get a pre-amp of 0 or close to 0.
One thing to note if doing this- while it's usually better to AutoEQ only up to 7,000Hz or so, if doing this you will result with a curve that is boosted in the high treble, as it's cutting everything else, and the high treble will just be left alone, relatively. So if doing this and it's a bit extreme, you may also want to add a negative high shelf from the frequency you stopped AutoEQ at, to bring the treble back in line.
Limiter may do it though, I don't find it to be an issue generally with Wavelet. But maybe it is if you have like +10dB peaks in there.