It is a problem with currently available solutions that binaural transmission, i.e. transmission between the two hearing instruments of a binaural hearing aid system, creates an additional latency to the hearing aid processing because of signal buffering, quantization, coding, synchronization, etc. Typically, the hearing instruments may either only transmit or receive audio signals at a given time instant. This means that in order to have hearing instruments operate synchronously within a time slot, the hearing instruments are required to wait until the audio signal packages have been transmitted and received at both hearing instruments.
By only transmitting the audio signal in one direction, such processing delay may be reduced, because waiting for an audio package, which is transmitted in the opposite direction will not be necessary. Therefore, in order to design binaural signal processing algorithms (e.g., binaural noise reduction algorithms) which make use of signals sent only in one direction, there is a need to provide a solution to the problem of how to decide, at any given moment, in which direction (i.e. from which hearing instrument to which hearing instrument) the signal is to be sent.