I would like to merge both fir_low pass filter example and the audio play back example. Could anyone help?
If you were trying to apply filter for all individual channels, then you need to split the ADC samples according to the channels. Do individual channels filter configuration before enabling ADC and DAC. And inside ProcessBuffers()function enable fir by calling adi_fir_EnableConfig() API next to adi_adau1979_SubmitBuffer() API and copy the output filter samples to DAC.
If this information is not meet your requirements means, please let us know which mode you are using TDM or I2S and also let us know how many channels you need to process filter.