A hearing assistance device adapted for being arranged at least partly on a user's head or at least partly implanted in a user's head, the hearing assistance device comprising • an input transducer system comprising ∘ an audio input transducer for picking up a sound signal from the environment and providing an electric audio input signal, ∘ a first supplementary input transducer for picking up a sound signal from the environment and providing a first supplementary electric input signal, and ∘ optionally one or more further supplementary input transducers (SIT2; SITn) for providing respective one or more further supplementary electric input signals, • an output transducer for converting a processed output signal to a stimulus perceivable by said user as sound, and • a signal processing unit operationally connected to said audio input transducer, to said first supplementary input transducer, and to said output transducer, said signal processing unit being configured for processing said electric audio input signal, and said first supplementary electric input signal, and for providing said processed output signal, wherein said audio input transducer is adapted for being located in an ear of said user, and wherein the hearing assistance device is configured to operate in different modes, • a mode of operation at last partly determines the processing of the electric audio input signal and the supplementary electric input signal(s) by the signal processing unit, characterized in that • the signal processing unit is configured to provide that said processed output signal - in a normal mode of operation of the hearing assistance device - originates from said electric audio input signal, and • wherein the hearing assistance device further comprises a howl or feedback detector for detecting the occurrence or build-up of feedback howl, and wherein the signal processing unit is configured to provide that said processed output signal - in a feedback mode of operation of the hearing assistance device, where build-up of feedback howl is detected - originates from said first and optionally further supplementary electric input signals. • an input transducer system comprising ∘ an audio input transducer for picking up a sound signal from the environment and providing an electric audio input signal, ∘ a first supplementary input transducer for picking up a sound signal from the environment and providing a first supplementary electric input signal, and ∘ optionally one or more further supplementary input transducers (SIT2; SITn) for providing respective one or more further supplementary electric input signals, ∘ an audio input transducer for picking up a sound signal from the environment and providing an electric audio input signal, ∘ a first supplementary input transducer for picking up a sound signal from the environment and providing a first supplementary electric input signal, and ∘ optionally one or more further supplementary input transducers (SIT2; SITn) for providing respective one or more further supplementary electric input signals, • an output transducer for converting a processed output signal to a stimulus perceivable by said user as sound, and • a signal processing unit operationally connected to said audio input transducer, to said first supplementary input transducer, and to said output transducer, said signal processing unit being configured for processing said electric audio input signal, and said first supplementary electric input signal, and for providing said processed output signal, wherein said audio input transducer is adapted for being located in an ear of said user, and wherein the hearing assistance device is configured to operate in different modes, • a mode of operation at last partly determines the processing of the electric audio input signal and the supplementary electric input signal(s) by the signal processing unit, characterized in that • the signal processing unit is configured to provide that said processed output signal - in a normal mode of operation of the hearing assistance device - originates from said electric audio input signal, and • wherein the hearing assistance device further comprises a howl or feedback detector for detecting the occurrence or build-up of feedback howl, and wherein the signal processing unit is configured to provide that said processed output signal - in a feedback mode of operation of the hearing assistance device, where build-up of feedback howl is detected - originates from said first and optionally further supplementary electric input signals.