Rate matching algorithm and independent device synchronization

A hearing aid system wherein a data streaming device streams data to a hearing aid, the system comprising:

• a hearing aid;
• comprising a transmit coil, a receive coil and a microactuator, the receive coil adapted to receive signals from the transmit coil and transmit signals to the microactuator;
• the hearing aid adapted to receive data from a data transmission device, wherein the data received by the hearing aid has a first sampling rate;
• a buffer adapted to receive data from the data transmission device;
• an RWDiff signal which indicates the difference between the rate at which data is read from and written to the buffer;
• and
• a control circuit which compares the RWDiff signal to a predetermined RWIdeal quantity and generates an adjustment signal.

A method of maintaining synchronization when converting a sampling rate in a hearing aid, the hearing aid comprising a transmit coil, a receive coil and a microactuator, the receive coil adapted to receive signals from the transmit coil and transmit signals to the microactuator, the method comprising the steps of:

• receiving data from a data transmission device wherein the received data has a first sampling rate;
• converting the received data from a the first sampling rate to a second sampling rate, wherein the second sampling rate is a sampling rate usable in digital signal processing circuitry in the hearing aid;
• transmitting the received data to a buffer which holds the received data until it is read by the digital signal processing circuitry;
• calculating a RWDiff signal which is a function of the difference between the rate at which date is written to the buffer and the rate at which data is read from the buffer;
• using the RWDiff signal to modify the rate at which data is either written to or read from the buffer.