DriveLine does support voice commands. When I implemented voice commands in DriveLine, I experimented with an 'always listening' mode, but I felt like it wasn't reliable. So, to trigger DriveLine to start listening, perform a long-hold on the status-bar. The music will pause for a few seconds while you speak a command. I could probably add a Config setting to enable 'Always Listening' mode. I've got some other ideas for how to make it easier to use too. But the basic functionality is there.
For skin-specific commands, look for
Skin_SkinVoiceCommands.xml in the skin folder.
For generic DriveLine commands, look for
DriveLine_VoiceCommands.xml in the Settings folder.
I recommend testing both.