The article was written in the development of ideas from a previous work of the authors [5]. The task of automated quality control of voice templates, which were registered and stored in the Unified Biometric System is considered. A solution to the problem of timely updating of the collected templates is proposed, since over time they lose their consumer qualities. A new indicator of the acoustic quality of voice templates in the Kullback–Leibler information metric was investigated and a method for measuring it at the moments when users contacting the system with service requests was proposed. An example of the practical implementation of the proposed method is shown. Using the author's software, a full-scale experiment was conducted, quantitative estimates of the period for updating voice templates were obtained, and recommendations were given on their practical application. The results can be used to develop new and modernize existing systems and technologies for automated quality control and updating of biometric personal data templates.