According to reports in the Financial Times, the technology firm is reeling after a dossier alleging financial mismanagement at the firm was distributed to its shareholders.
Spinvox is understood to have called in financial experts Brunswick to help manage the media fall-out.
The appointment comes days after Spinvox extended retained agency Porter Novelli's brief (PRWeek, 28 July 2009).
The agency was tasked with helping to response to potentially damaging claims by the BBC about the company's technological processes.
The BBC story claimed much of the transcription of its voice messages to text is carried out by humans rather than, as Spinvox has always maintained, automated technology.
Brunswick refused to comment and Spinvox could not be reached for comment on the story at the time of publication.