DJM-S9 Sampler Volume knob

Hello.

I am routing audio from my software to the S9 USB 5/6 channels as per this config.

The audio can be routed through the sampler fx send/return and seems to go to the master after that, sweet. Though the position of the Sampler Volume knob doesn't impact the incoming signal.

Looking at this diagram from the end of the manual, the sampler volume stage doesn't seem to appear in the chain. Should I assume this knob does not control any amplification of signal? 

If so, it's exciting to be able to have another midi mappable knob on the top face of this mixer which does not also control mix functions when using the S9 outside of Serato.

Many thanks,

-NC