I have a sparky board with the 2.1 Piano Dac. It works perfect with a subwoofer, but not without. If I select a 2.0 Piano Dac, the High Pass Filter is still working, so the lower basetones are missing. There must be a way to select 2.0 mode on the 2.1 Dac, to disable this filter.
On Volumio it works. But Volumio is not my cup of tea.