Tinny music emanating from headphones is an everyday hazard, especially on public transport. If you are using headphones, be aware that your music - distorted, percussive, maddening - may be painfully audible to your next door neighbour, and adjust the volume accordingly. But, for all their failings, headphones should always be used. It is the height of bad manners to inflict music, or a noisy DVD soundtrack, on other people in a confined public place.

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