Here is the list of pins that are used by Pisound:
Pin 11 - The Button GPIO input, when button is pushed down, it gets connected to GND, so the pin should be configured as a GPIO input with pull-up enabled.
Pin 19, Pin 21, Pin 23, Pin 24 - MOSI, MISO, SCLK, SS for SPI communication, the devkit should be the SPI master.
Pin 33, Pin 37, Pin 36 - OSR0, OSR1, OSR2 GPIO output pins for configuring audio ICs.
Pin 32 - audio reset control, GPIO output.
Pin 35, Pin 40, Pin 38, Pin 12 - I²S pins PCM_FS, PCM_DOUT, PCM_DIN, PCM_CLK.
Pin 22 - Data Available pin, should be configured as a GPIO input with an interrupt on rising edge.
Pin 18 - Controller reset pin - GPIO output.
HAT I²C EEPROM containing DT overlay for RPi is attached on pins 27 and 28 - just in case mentioning here.
You may find all uses of the mentioned GPIO pins in the Pisound kernel module source code here. Search for ‘gpiod_get_index’. In case ‘gpiod_to_irq(data_available)’ does not return a proper value on Jetson Nano, this part must be modified to use the correct value.
And for reference, current overlay for RPi is available here.