Stream grabbing: Display the stream locally: No volume control

[DavidEsp]

I successfully used VLC (3.0.16) on my Mac to grab a stream.
Also, when I enabled/checkmarked [Display the stream locally] it additionally played at the same time

However, when doing that, the played volume was fixed at full level.
VLC's volume control was greyed-out (and ineffective), and (unsurprisingly in that case) the volume control hotkeys had no effect either
Annoying since sometimes, during the grab-session, I wanted to play other material.
Hence simply lowering the system's (macOS) volume control was not a useful workaround.
I ended up having to disable [Display the stream locally] and play the same stream another app (not VLC).
Hence two instances of the same stream: one to VLC (grabbing), one to another app (playing).

What did work was using Audio Hijack, using its graphical window to connect VLC's output to a volume control to system output.

Workaround request - anyone know any way to achieve this in VLC on its own? (in case I've missed something) or have any further workarounds?

Feature request - to change VLC so its volume control does work in this context (to affect only the playing - not stream-grab - volume)