Is there a way to control Alsa volume through software if I2S Dac (e.g. old Hifiberry) doesn't support software volume control (amixer is empty and if you add mixer it won't affect anything)?
While with MPD 5 can control volume for what is played within MPD but it doesn't affect volume if its played outside it, from other sources, such as
spotify-connect lib, which uses Alsa mixer to control volume. Is there a way to it (or direct audio signal to MPD)?