I ran a quick test as to whether one ear was better than the other by taking each ear-piece out in turn. The sound was very faint either side. But I noticed one strange thing. For a brief moment, when one ear-piece slipped in my grasp, I had nothing in either ear and yet could still hear.
Ladies and gentlemen I solved the problem by inserting the jack into the socket just a little bit more. After a click the sound now came out of the earphones rather then my pocket.
For many hundreds of metres I had been broadcasting to the nation the hip and happening sound of a podcast of BBC Radio Four's science programme The Infinite Monkey Cage.
I am so cool.