I try to use a Digi+ (standard) on a RPi 3B.
For a short moment, I saw some level meter activity on my output device but after that, I couldn't get it to work anymore.
I checked I2S clock and data signals which look fine, also there's some activity during initialization of the WM8804.
The output signal at the RCA connector however looks distorted. I see an interfering pulse occuring with a constant frequency of 1 / 29.8 us.
See the attached picture. I think that this might prevent proper locking of the signal. The DSP amplifier I am using works fine with the S/PDIF output of my CD Player with exactly the same cable.
Any idea what might cause this?