Yeah, so picked it up yesterday

I wanted some fatter, warmer sound in the bridge compared to the JB / Distortion I have at the moment. Less highs and perhaps less output, but not necessary. Has an Alnico II and it's slightly overwound, ~19Kohm so it's quite hot, ended up with more output. Very good balance of bass, low mids and high mids, definitely less highs than the Distortion. Cleans up really well when rolling the volume back and great single coil sound too, not piercing at all compared to the JB in the same guitar. The notes are singing, overall I like it a lot. But there's a catch: in humbucker mode, at high gain it has a rather pronounced hum noise which magically disappears when I roll back the volume a little bit. Say from 10 down to 8.5-9. Comparing it to the other pickups I have, the hum noise feels like this:
- Duncan Distortion bridge & DiMarzio Gravity Storm neck: both dead quiet.
- Full Shred neck: just a little bit of hum, barely noticeable.
- JB and '59 neck: bit more hum than the FS, all on par, noticeable compared to the DD and GS above.
- The rewound pickup: bit noisier than the JB & 59s
The thing when rolling the volume back to tame the noise is, I get rid of the hum but I like it even more, it sounds fuller, there's probably less mids?
I don't know what to do, I like its character as it is but I could do with less hum noise

I've rechecked all the wiring and I don't think I have a grounding problem due to soldering. Is it because it's overwound? Or perhaps less than perfect grounding?
Curious what people think.