There is currently no traffic law in BC that explicitly makes this practice illegal. It is not a wise practice however, and a defensive driver would not do so. The music (or podcast) may prevent you from hearing something important or distance you from the task of driving.
Effective January 1, 2010 when using a headset with a hands free cell phone the new legislation says that only one ear may be used, but this does not apply to the operator of a motorcycle.