PSA: My bluetooth controller stop working with the message:
bluetooth hci0: Direct firmware load for mediatek/BT_RAM_CODE_MT7961_1a_2_hdr.bin
on kernel 6.9. Downgrading to 6_8 fixed it for now.
I think there’s something wrong with the way firmware works in NixOS, I haven’t hit this yet, but I ran into a very similar issue before. If you don’t mind doing terrible things, last time I was able to fix it by patching the Nix store directly. It’s not what you should do, of course, but i did do it and it worked.
If anyone knows why this happens, I’d love more information.