Has anyone heard of antiseptic wipes? The system on my Boeing works best when both headsets are of the same type, preferably those supplied with the aircraft. When I use the headset supplied and my co has his own noise reducing set, I have to endure many hours of hissing, avoided by the simple expedient of turning him down.
A quick wipe before each flight for the last thirty something years and no ear or lip infections. Spend the money on a good watch!
£3000.00 for a Breitling, he was robbed!