A Rule for Karabiner-Elements Complex to Control Mute/Unmute in Zoom with Eject Key

zoom.json

{
  "title": "Zoom",
  "rules": [
    {
      "description": "Map eject to command + shift + a",
      "manipulators": [
        {
          "type": "basic",
          "from": {
            "consumer_key_code": "eject"
          },
          "to": [
            {
              "key_code": "a",
              "modifiers": ["left_command", "left_shift"]
            }
          ]
        }
      ]
    }
  ]
}