Quote:
Adding home-made components to an aircraft system (the RT/intercom) is most certainly not acceptable
B.S.
Headsets are unregulated.
What has regulation to do with it? Just ask your Flight Ops Director for approval to alter/add to the headset and for permission to use the equipment which you have purchased and cobbled together and there should be no problem, apart from the fact that you risk losing your radio telephony licence.
As a captain I would refuse point blank to let anyone use equipment like this without such permission.
PP