Quote Originally Posted by DD4WH View Post
Oh, did not know that. I left SCL of the DAC unconnected.
From the PCM5102A datasheet, "The serial audio interface typically has 4 connections SCK (system master clock), BCK (bit clock), LRCK (left right word clock) and DIN (data). The device has an internal PLL that is used to take either SCK or BCK and create the higher rate clocks required by the interpolating processor and the DAC clock. This allows the device to operate with or without an external SCK."

When testing with the Convolution object by DerekR I experienced strange crackling noises. Could it be that this is caused by this?

I will try to connect SCL of the DAC to pin23 of the Teensy 4.0.
I'm not sure the clicking noise you heard was this or not. But definitely worth trying.