After reading on some canbus control packages, I'm confident that a raspberry pi based bluetooth receiver can be made so that it understands vehicle speed and increases volume as the vehicle speeds up (to compensate for road noise), also reacts to steering wheel volume / track commands.
Unfortunately, I've never dealt with Pi, so I don't even know the proper keywords to search for. Has something like that been figured out? Either at a DIY level, or as a ready made / pre-build solution.
I've never dealt with Pi... Raspberry Pi is a Linux computer ... have you dealt with Linux?
understands vehicle speed and adjusts volume accordinglycan easily mean that you are asking about adjusting the vehicle speed level ... this is an international site and language translation can pick misleading words