Problem with Allo relay attenuator plug-in (or with relay)

The output volume is very weak, my professional speakers allow you to adjust the gain, but then it makes a lot of noise. It is also very difficult to adjust the volume with volumio control volume. Is it necessary to make some other adjustment or is it that I am doing something wrong? If this is the correct volume I think Relay Attenuator is not for me, and maybe it is only advisable for allo volt.

Thanks

I just bought this allo attenuator to put it above raspberry 2, piano 2.1 and Kali.

Audio passes through, but i cannot attenuate volume via Volumio (attenuator plugin has been installed of course) or even Bubbleupnp, which is the goal of this card.

I switched volumio configuration from 2.2 (stereo subwoofer) to dual canal as recommanded, but it still doesn’t work.

Maybe i missed something.

Has somebody a similar config ?

Sincerely

François