SBC codec is parts of the A2DP (Advanced Audio Distribution Profile) by Bluetooth and allows wireless transmission of audio signals between a transmitter and a receiver. We can generally differentiate between A2DP-SRC in the source and the A2DP-SNK in the sink. Unlike optionally supported codecs and transmission formats such as MP3, AAC and aptX, the devices must implement SBC. Since the SBC codec is lossy, transmitting audio signals may cause an audible loss of quality. At 345 kilobit per second, however, SBC has a very high maximum bit rate and reduces almost the entire audible loss. Sophisticated audio transmissions, however, often use different codecs. The SBC codec can easily be used for the already limited frequency in telephony.