Usually one earbud is the primary device and the other is the secondary. The primary links with your phone and communicates with the secondary. I’m not saying it’s impossible to replace an earbud. But it would require some firmware support for this re-pairing. I hope FP will introduce this sometime. Because I don’t think any other company offers this. I think the second generation earbuds will be modular, just like the first Fairphone wasn’t modular but mainly focused on fairtrade and long use. By then I probably have to replace my old Jabra earbuds anyway.