It's not the first time we've heard such news, but iPod headphones could offer a serious risk to people with surgically implanted heart monitoring devices, such as pacemakers or defibrillators, a new study has revealed.

Magnetic interference from MP3 player headphones could prove fatal by temporarily deactivating a device, revealed the research, that involved 60 patients and 8 different models of headphones.

The research team said users with MP3 players should keep headphones at least 3cm away from their pacemaker or defibrillator.

"For family members or friends of patients with implantable defibrillators, they should avoid wearing headphones and resting their head right on top of someone's device", said William Maisel, director of the medical device safety institute at Beth Israel Medical Centre in Boston, Massachusetts.