Volume control with dac USB/Toslink

My volumio is V3, My DAC SMSL M100 that is compliant with the hardware volume control.

When I connect the dac via the USB port I can set up in volumio the hardware volume control
When I connect the dac via Toslink, I cannot, only software volume control is proposed.

It that mean the hardware volume control only available if we connect the dac on usb ?
Did I miss something in the setting to allow the hardware volume control when connected via toslink ?

Help will be appreciated


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the TOSLINK interface does not support hardware volume control, it is an old standard only meant to provide the digital audio stream.

if you can connect your DAC via USB, it is recommended to do so

Thanks, it is what I thought !

When I connect via USB, every is fine, except in Hres, 98 & 192kbps I have some noise (clicks) at the begenning of the track and sometime, never … The same Dac connected to my laptop does not produce the noise.

Any idea ?

Thanks for your help