Listening device and a method of monitoring the fitting of an ear mould of a listening device

A method of detecting whether an ear mould of a listening device is correctly mounted in the ear of a user, the listening device comprising

• a forward path between an input transducer for converting an input sound to an electric input signal and an output transducer for converting an electric output signal to a stimulus perceived by the user as an output sound, the forward path comprising a signal processing unit for applying a frequency dependent gain to the electric input signal or a signal originating therefrom and for providing a processed signal, and feeding the processed signal or a signal originating therefrom to the output transducer;
• an analysis path for analysing a signal of the forward path and comprising a feedback estimation unit for estimating a feedback path from the output transducer to the input transducer,
• the method comprising
• a) providing a long term estimate of the feedback path;
• b) providing a probe signal, which can be relayed to the environment of the listening device by the output transducer;
• b) providing an estimate of the current feedback path based on said probe signal;
• c) comparing the long term feedback path estimate with the current feedback path estimate, and providing a measure of their difference, termed the feedback difference measure FBDM.