All India Radio (Russian Service, DRM, end of broadcast) received in London, UK

Terrible mains audio hum in DRM mode! Someone should show this to AIR's sound engineers - they should add a few ferrite chokes to their audio cables! 15140 kHz, 02/08/2014 1715 UTC. Toshiba Encore 8", FunCube Dongle Pro+, SDR#, Dream, 6m wire antenna, outdoors.