diff --git a/Library/Homebrew/dev-cmd/audit.rb b/Library/Homebrew/dev-cmd/audit.rb
index 1f58971355..d964db2a2b 100644
--- a/Library/Homebrew/dev-cmd/audit.rb
+++ b/Library/Homebrew/dev-cmd/audit.rb
@@ -206,14 +206,17 @@ module Homebrew
       require "cask/cmd/abstract_command"
       require "cask/cmd/audit"
 
+      # For switches, we add `|| nil` so that `nil` will be passed instead of `false` if they aren't set.
+      # This way, we can distinguish between "not set" and "set to false".
       Cask::Cmd::Audit.audit_casks(
         *audit_casks,
         download:              nil,
+        # No need for `|| nil` for `--[no-]appcast` because boolean switches are already `nil` if not passed
         appcast:               args.appcast?,
-        online:                args.online?,
-        strict:                args.strict?,
-        new_cask:              args.new_cask?,
-        token_conflicts:       args.token_conflicts?,
+        online:                args.online? || nil,
+        strict:                args.strict? || nil,
+        new_cask:              args.new_cask? || nil,
+        token_conflicts:       args.token_conflicts? || nil,
         quarantine:            nil,
         any_named_args:        !no_named_args,
         language:              nil,
diff --git a/manpages/brew.1 b/manpages/brew.1
index 07c060d121..3830731697 100644
--- a/manpages/brew.1
+++ b/manpages/brew.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BREW" "1" "October 2021" "Homebrew" "brew"
+.TH "BREW" "1" "November 2021" "Homebrew" "brew"
 .
 .SH "NAME"
 \fBbrew\fR \- The Missing Package Manager for macOS (or Linux)