According to the TIO, overall complaints for the July to December period increased nine per cent, driven by a sharp increase in mobile phone service issues. Mobile phone issues alone increased some 20 per cent.

Commenting in TIO newsletter TIO Talks, ombudsman, Simon Cohen, said the results came as a disappointment, considering the positive beginning to 2010.

“The increase, entirely reversing the positive trend seen in the first half of 2010, is extremely disappointing,” Cohen said. “December 2010 was one of the busiest months the TIO has ever seen and the trend has continued into 2011.”

One reason for the spike in complaints is the networking issues Vodafone has experienced, with the telco after it experienced a series of technical problems and outages.

“Customer frustration with Vodafone is understandable,” Cohen said. “It is one thing to have a service problem, but what is particularly concerning is when consumers cannot contact someone to have their problems sorted out.”