I want to raise an issue. Not sure if it's hardware or software related.
I have an Amp100 with DSP optical input enabled and set to automatically switch-off other inputs. Optical input is connected to TV.
When streaming with DNLA or Spotify directly to HiFiBerryOS, I hear a crackling noise similar to a dusty needle on a turntable. This is with TV turned off.
If I then turn on TV and stream spotify to TV instead, HiFiberryOS switches to optical input and music plays without the noise.
If I turn off the optical input in sources, I can stream to HiFiBerry without noise. This is a work around that is OK but takes away the convenience of automatically playing TV through Hifi speakers.