The place for technical discussions about GA and flying.
Forum rules: Technical discussions about GA only, please.

Just wondering if anyone with an electrical background in headsets etc might be able to let me know what (if anything) the blue wire is for in a David Clark H10-13X Headset.

Mine has broken in the module box, but the wiring diagram for the headset makes no reference to a blue wire and when tested the headset seems to be working fine.

Only to re-solder the wire together would be very fiddly and if this is a surplus wire I'd rather not bother.