i've got a pair of pro-luxe active noise cancelling headphones which i
use on the train. But they pick up any nearby 900 mhz phone signals.
they're not bothered by 1800 mhz and 3G signals so my phone doesn't
affect them but i'm surrounded by iPhone users on O2! I'm going to
have a look at maybe adding some screening (foil?) to the right
headphone as it seems to be direct pick up by that (where the
amplifier is) rather than through the cable.