Sebastien, does this look correct to you?

I think it was designed to look properly centered when all the volume bars are visible, so it will look like it's shifted slightly left when not at full volume. Not sure there's anything we can do to fix that, since we want the speaker part to stay in place as the volume changes.

Yes the icon is balanced based on the full volume glyph. 

Offsetting it here would offset it in full volume and as Tom said we cannot make it move based on its state as it would look jarring.

Thanks for the confirmation!