A hearing assistance system with a low-power mode

The application relates to a portable hearing assistance device comprising an input unit, an output unit, a forward path between the input unit and the output unit, and an energy source for energizing components of the hearing assistance device. The application further relates to a method of providing a low-power mode in a hearing assistance device and to the use of a hearing assistance device. The object of the present application is to provide an improved concept for switching a hearing assistance device to or from a low-power mode. The problem is solved in that the hearing assistance device comprises a control unit configured to control the activation (or deactivation) of a low-power mode of operation of the hearing assistance device, wherein - when said low-power mode is activated - the draw of current from said energy source is reduced compared to a normal mode of operation of the device, the activation (or deactivation) being influenced by a combination of at least two different control input signals to the control unit, each control input signal being a signal selected from the group of signals comprising 1) signals relating to a current physical environment of the hearing assistance device, 2) signals relating to a current acoustic environment of the hearing assistance device, 3) signals relating to a current state of a wearer of the hearing assistance device, and 4) signals relating to a current state or mode of operation of the hearing assistance device and/or of another device in communication with the hearing assistance device. This has the advantage of improving functionality of the hearing assistance device. The invention may e.g. be used in hearing aids, headsets, ear phones, active ear protection systems, etc., or combinations thereof.