Right-click → Mixing & Effects → Switcher.

Switcher
A/B Switcher
Input
Output

Each side has sets - stereo port pairs, up to 8 per side. One set per side is live; the live one is filled in the brand colour. A new Switcher has one set on each side, both live.

DoHow
Make a set liveClick it
Silence a sideClick its live set
Add a set+ Add under the side
Rename a setIts pencil icon
Remove a setRight-click it
  • Sets on the Out side switch one source between destinations, e.g. two pairs of speakers; sets on the In side switch sources into one destination.
  • Switching fades over about 15 ms, so it does not click.
  • Removing the live set leaves that side silent. Each side keeps at least one set.