Hello,
attached is a small file that mutes the sound at boot time to avoid
raising suspicion by startup sounds or audio/video files accidentially
played.
(see 
https://tails.boum.org/bugs/Sound_not_disabled_by_default/)
Sincerely,
JohnDoe
>From 137d52ecf02b0de65fbe1a1a8c3f7ad84a99beae Mon Sep 17 00:00:00 2001
From: use <user@localhost>
Date: Thu, 26 May 2011 13:36:15 +0200
Subject: [PATCH] Add a small script that sets the audio volume to zero at
 boot time.
---
 .../lib/live/config/205-asound-mute                |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)
 create mode 100755 config/chroot_local-includes/lib/live/config/205-asound-mute
diff --git a/config/chroot_local-includes/lib/live/config/205-asound-mute b/config/chroot_local-includes/lib/live/config/205-asound-mute
new file mode 100755
index 0000000..b6f7e7c
--- /dev/null
+++ b/config/chroot_local-includes/lib/live/config/205-asound-mute
@@ -0,0 +1,5 @@
+#!/bin/sh
+# ... to mute the audio at bootup
+
+/usr/bin/amixer sset Master mute
+
-- 
1.7.4.4