Trustees of the Christadelphian Magazine and Publishing Association, based at Shaftmore Lane, alerted the Charity Commission after noticing the irregularities in their finances last year.
A spokeswoman for the Charity Commission said: “The Christadelphian Magazine and Publishing Association reported a serious incident to the Charity Commission in October 2011 concerning financial irregularities within the charity.
“The trustees advised us they were conducting an internal investigation into the irregularities and had taken steps to review the charity’s financial controls and governance.
“We have recently received further information from the charity about their internal investigation, which we are currently considering.
“We are not currently aware of any police involvement, however this is something we will take into consideration when looking at the information from the charity about their internal investigation.”
Police confirmed that they were not currently investigating.
The company, which has nine employees, has been publishing and distributing the magazine to Christadelphian religious groups around the world since 1869.
In its latest financial documents, Christadelphian Magazine and Publishing Association is shown to have assests worth nearly £1.5million with an income of £848,000. It paid £363,000 last year in charitable spending.