Audiophilia strikes again. People are prepared to strap things to their heads or even put things right in their ears that are connected to 500V power supplies or driven by amplifiers that have been created deliberately by self-proclaimed 'eccentric mavericks' to be different i.e. DC-coupled, high powered, 'discrete', 'novel feedback topology', etc. For all we know they may oscillate ultrasonically or, in the event of a component or connection failure put the full power supply out onto the headphones. These people have previously created amplifiers that visibly warped headphone diaphragms at power off.
Such devices should really be designed almost like medical equipment or have idiot-proof fail-safes.