I would like this option for the other Mini/Pro(+) streamers as well. Ultimately, it's just software.
Having the option to select between two volume modes sounds like the way to go.
If WiiM does not want to switch between the 2 use-cases outlined below because this might overstrain some users, a selection of step-size would do. The default value could be 1dB/step.
@canard (separate volume control downstream) would use e.g. 0.3dB/step and I would probably choose 0.8dB or 1dB per step in my setup where the WiiM is the only volume control.
Use-case 1:
Some setups have a separate analogue volume control, thus only minor adjustments are made with the WiiM.
(this is true of my other setup, which incorporates a legacy-style analogue integrated amplifier).
Proposal: similar transfer curve as implemented now (small steps in the upper region), however 0.3xdB/step seems unnecessary to me; 0.5dB/step would do. WiiM seems to do their volume control in their uC because
AK4493SEQ can do 0 ... -127dB in 0.5dB steps.
PCM5121 can do +24dB ... -103dB in 0.5dB steps
Use-case 2:
Others control the volume digitally with the WiiM only:
Proposal: constant steps down to ca. 100dB attenuation. In case we're limited to 100 steps, 1dB/step is nice .
My Arcam A32 has an analog (digitally controlled) volume control and allows 3 different resolutions (standard (3dB?), fine (1dB) and reference (0.5dB) down to 72.5dB attenuation. I tried 0.5dB/step, but ended up using "fine", so 1dB/step would be fine for me. No idea why they limited the attenuation to 72.5dB, the IC can do -111.5 to +15.5dB in 0.5dB steps.
What do you think?