So just an update here. I just set my Car Volumio up with bluetooth controls and there was no need to install any packages. everything was already installed. Im running the Touch diplay and Now playing plugins.
Steps to get this working took about 2 minutes:
hciconfig -a
bluetoothctl
[bluetooth]# power on
[bluetooth]# pairable on
[bluetooth]# scan on
(start pairing on the Bluetooth controller, then look for your device)
[bluetooth]# pair xx:xx:xx:xx:xx:xx
[bluetooth]# trust xx:xx:xx:xx:xx:xx
[bluetooth]# connect xx:xx:xx:xx:xx:xx
sudo nano /etc/triggerhappy/triggers.d/audio.conf
(i commented out default config and added below)
KEY_PLAYPAUSE 0 /usr/local/bin/volumio toggle
KEY_NEXTSONG 0 /usr/local/bin/volumio next
KEY_PREVIOUSSONG 0 /usr/local/bin/volumio previous
sudo /etc/init.d/triggerhappy reload
rm /lib/systemd/system/triggerhappy.socket
sudo reboot
then you have working Bluetooth controls. I am using this controller: