In relation to overseas-based sellers, the regulator said it had written to a number of companies as a "pro-active measure" to highlight that sending audio jammer to Australia could result in them being intercepted. It said some of the overseas sellers it contacted now had disclaimers on their websites advising purchasers to check the legal requirements of the country that they resided in before buying a jamming device.

Since first publishing a report on an American using a mobile phone jammer on a bus in Philadelphia in the US to stop fellow passengers making mobile phone calls, many Australians have come forward to Fairfax saying they used jammers too, in addition to people already mentioned as using them.

One claimed he bought a jamming device about two years ago in London at a gadget shop and has it stuck under his dining room table to prevent his teenager from using Facebook whilst having dinner. "They have never worked it out," they said.

A second claimed he bought his jammer to "play practical jokes on friends" but said he never tried it on the bus, train or in public. A third, a Sydney man in his late 20s who Fairfax has previously quoted, claimed he carried his portable rf jammer "most days" on his train commute to Sydney which lasts about 1 hour and 45 minutes each way. He said he used it about 2 to 3 times a month.