1. A hearing assistance device for use by a listener, comprising: a microphone configured to receive sounds from an environment of the hearing assistance device and produce a microphone signal representative of the sounds; a receiver configured to produce output sounds based on an output signal and transmit the output sounds to the listener; and a processing circuit configured to produce the output signal by processing the microphone signal, the processing circuit including: a plurality of functional modules; an auditory condition detector configured to detect one or more auditory condition values indicative of one or more auditory conditions each related to an amount of computation needed by one or more functional modules of the plurality of functional modules to each perform at an acceptable level; and a computational resource allocator configured to dynamically adjust one or more calculation rates each associated with a functional module of the plurality of functional modules based on the one or more auditory condition values.