Aegon-owned network Origen chief executive Mike Kirsch has stepped down with immediate effect.
Executive chairman for distribution Rob Waller will take over as acting interim chief executive until further notice, said an Aegon spokesperson.
Origen posted a loss before tax of £2.9m in March after a £1.9m provision for a review into advice suitability impacted on the business' bottom line.
The Origen board began a review of the firm's systems and controls and the suitability of regulated advice given to clients in 2011, with the aim of "identifying any past failings and embedding best practice".
Origen said it expects the work to be completed this year, and, along with the £1.9m recognised in the accounts , it has made a £320,000 provision against this review for 2012.
The 2012 loss of £2.9m is an improvement on the company's results in 2011, when it posted a £3.5m loss.
However income for the year fell to £16.2m, down 8% from £17.6m in 2011, largely as a result of the absence of larger corporate advice projects, the firm said.
Average revenue per adviser increased to £227,000 last year, up from £211,000 for the previous year.
Excluding the cost of the suitability review and redundancy costs of £181,000 - down from £634,000 in 2011 - administrative expenses fell 25% from £2.6m to £1.9m.
During last year, parent company Aegon gave Origen a cash injection of £4m. Origen is forecasting a loss for the year ended 31 December 2013.
Putting the tech into protection
Square Mile’s series of informal interviews
Fallout from Haywood suspension
Launching later in 2019
£80bn funds under calculation