Hi everyone.
I’m using rpi3 and allo boss v1.2 dac with volumio. I dowloaded volumio app to my android car multimedia and control volumio with it.
But i cant control volume with car push button. Is there any solution?
UP
Can you give some more information on the Android Car Multimedia system you are using, how things are wired up, and what you want to achieve?
From the little info you give, I we are talking in-car audio, using an Android Car Multimedia system to replace the normal radio, and the Pi + DAC hooked up to the multimedia system via a tulp cable. Correct?
In that case, the volume buttons of the multimedia system should simply control the volume just as it would when listening to radio or having any other device connected to the aux. That is completely independent of Volumio.
Pi and allo boss wired to amplifier with rca cables. I connect to pi with volumio android app with my car multimedia (wireless). I know its independent from volumio but is there any solutions to control volumio volume? For example software something?
Good, so my first assumptions were correct. Now which part does not work, and what do you want to achieve?
The volume buttons on your multimedia system control the output volume of the amplifier, just like with any other source like radio etc. That is enough to control volume, right? I don’t see why you need software volume control on Volumio’s end.
Because volume control is distracting when driving. I want to control it with steering wheel push bottons.
The volume buttons controls only multimedia’s volume. But rpi3 is direct connect to amplifier.
I need to control rpi3 volume with my steering wheel buttons.
You will need a very complicated setup and custom coding:
- Can bus adapter for PI3
- Custom code to catch the right CANBUS messages for volume
Good luck 
So as it is connected now, Volumio always blasts its music on full volume? That is definitely not the right way to connect an aux to an amplifier.
Can’t you connect Volumio through the Aux-input of the multimedia system? That way you can control the volume through the buttons. I’m sure it has an aux input.