The indicator light of the KA3 can indicate the sampling rate of the music that is playing. Here are the details.Indicator light Sampling rate (digital input): ≤48kHz - Blue light constantly on Sampling rate (digital input): ＞48kHz - Yellow light constantly on Sampling rate (digital input): DSD - Green light constantly on When the color of the indicator does not correspond to the sampling rate of the track , please check whether the playback device or software setting is correct and check whether there is SRC.