Pi4 digi hat

[Tim Curtis]

Best way to troubleshoot:

1. Install stock Raspbian Buster Lite 2019-09-26
https://www.raspberrypi.org/downloads/raspbian/

2. Install Linux kernel 4.19.75

Code:

echo "y" | sudo PRUNE_MODULES=1 rpi-update d9321aceacfc6619b4238c6c764203b1122f2f9b

sudo rm -rf /lib/modules.bak
sudo rm -rf /boot.bak
sudo apt-get clean

3. Configure the correct overlay for the audio device: 
- Hifiberry Digi/Digi+ = hifiberry-digi
- Hifiberry Digi+ Pro = hifiberry-digi-pro

Code:

sudo nano /boot/config.txt

# Add the line below to the end
dtoverlay=hifiberry-digi

Save the file
Reboot

Then examine the boot log for errors trying to load the overlay

Code:

dmesg

If the overlay fails to load with errors then submit a bug report to Hifiberry with the list of steps that they can use to reproduce the issue.