cyclic_fondler, What!
I have used these headsets for years and have never had any problems. Like EN48 says, just don't wear them during start-ups, and if they insist then have them turn on the ENR once the engine has started up!
When I was teaching students or instructors didn't put headsets on till the radios were on.
I have used them a number of times and love them but I've also had to run out and wave and get the attention of students who haven't noticed that the engine is screaming because they can't hear it.