Hi. I am trying to figure out why the faders are still active while the audio is turned down, no sound when turned down, but fader is not affected either way. Do I get the audio signal from some other source in Cubase 9?
Best.
Hi and welcome to the german forum 
I suspect you have ghosts in your machine 
Seriously, there are many possible reasons for this behavior.
Maybe you have a delayed soundcard output, maybe you have a (low) outfading reverb effect, maybe your input channel is open (!?), maybe you have ‘unhearable’ (bottom) noisefloor, […]
See attached pic. I suspect it maybe due to some signal being sent from somewhere, I can’t seem to find it. All the audio tracks respond to the faders, but when taken to zero the indicators are still operating.
pre / post meters !