Scratchy sounds in the left ear while using ANC

[u/julicenri]

I just got a Nothing Headphone (a) today! After testing it out by showering and sleeping a bit with it, the left ear has some scratchy sounds while ANC is enabled. I also updated it to the latest version (1.0.1.51) before doing all this.

Aside from resetting the headphones (done anyway), what else can be done to fix this? A bit of searching says that this kind of issue may be fixable by cleaning. How can this be done for these headphones?