Player gain control as volume control in Desktop Companion App

[seadowg]

It would be great to be able to allow a way to have the volume slider in the Desktop Companion App (above) control the app's Sendspin player's Output Gain (as in DSP Settings for the player) instead of the system volume level.

This would be helpful when listening to music in the background while on a call or playing a game. Also, it helps in situations where the player's volume is much louder/quieter than other applications on the computer even when they are not being used at the same time to minimize how often you have to play with system volume. Currently, you need to use a system level mixer to deal with these scenarios and some environments (like macOS) don't have this as a built-in feature.