So my set got channel imbalance (left side was quieter), and I thought it was most likely due to the damper getting dirty/wet. I tried to clean it, but ended up damaging it (yeah, I'm dumb and I suck). Now the channel imbalance is gone, but the left side sounds shouty as hell.
There's no warranty anymore and I contacted Moondrop about the repair, but it might end up costing up to $200. I asked if they'd sell me just the damper, but they said no.
Now I want to see if I can order it from some of the DIY sellers from aliexpress and try to repair it myself, before I buy just the left earbud from Moondrop.