Winter is coming for your upper mids. How will you save it?

Seriously though; today I noticed a distinct change in my HD650’s as my house was cold and ended up wearing my hat indoors. I’ve got plenty of other choices but it did get me thinking as to whether I could account for a hat by eq. I don’t really have a suitable portable headphone amp for this so thought I’d ask this community if anyone has thought similar and acted on it?