Siemens has received a blow to its efforts to revive its loss-making mobile phone unit after it issued a warning that some of its flagship handsets could cause hearing damage. The faulty handsets may emit a piercing tone, that could prove harmful when a call is terminated due to low battery power. Robin O'Brien Lynch reports

O2 is urging all its customers with the Siemens 65 range of phones to deactivate the tone and advised its stores to stop selling the handsets until further notice.

Siemens stressed that the error might occur in very rare cases and that there was only a very slight chance of hearing damage. "This is a software problem that can only occur in rare and unlikely cases of usage, and, even then, the danger can only arise if the phone is held directly to the ear while the melody is playing," said a spokeswoman for Siemens Ireland.

"We're not planning to recall any of the handsets. We don't know how many of the phones have been sold in Ireland, but we are working closely with O2 on the issue."

According to 02, which carries the C65, CX65 and M65 models, the number of customers using the phones is "small". The C65 is the most popular of the faulty handsets and has been on sale since July. Neither Vodafone nor Meteor carry the line.

The news comes at a bad time for Siemens, which earlier this month announced that it was banking on the new 65 range to boost flagging mobile sales.

"It is simply too early to tell whether this will adversely affect profits. We will have a dent, but not a slump (in unit sales)," said a spokesman for the parent group. The unit posted an €88 million loss in the quarter to end-June.

To deactivate the melody, users need to select the "Setup" item in the main menu, then select "Ringtones", "More Melodies" and, finally, "Shutdown Melody", which can then be turned off.