Be able to selct virtual output devices

For the virtual devices installed by applications, they do not show up in output devices list. I whish we could have the option to add virtual devices in addition to physical devices. The reason is some apps provide a virtual devices that provides more granular control on eq or volume. For example I would love to use Background Music to control volume for each app on all my speakers and headphones. That means I would like to lock the output device to Background Music using Suohai.

Currently, Suohai is able to detect all devices having input channel, but virtual devices with both output and input channels are categorized as input devices i.e. Background Music. Therefore they only show up under input devices but not output devices.

I would like to see them show up and be selectable in the output devices list

Thank you very much for making locking audio devices available at the first place

Hey, first of all, nice job on this!
This note intent to propose the persistence addition, in order that you don't need to re-select your previously selected choice every time you restart your mac.
That addition would be just perfect for this tool.
Thanks.

Is it correct to assume that Option-Click on the sound icon in the menubar allows you to do the same thing that this app does?