[FE training-materials-updates] Thirdparty lab: add warning

[Michael Opdenacker]

Repository : git://git.free-electrons.com/training-materials.git

On branch  : master
Link       : http://git.free-electrons.com/training-materials/commit/?id=b45a9f0f76b70a056905e0b90d4fa5ff9d7aaae2

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commit b45a9f0f76b70a056905e0b90d4fa5ff9d7aaae2
Author: Michael Opdenacker <michael.opdenacker at free-electrons.com>
Date:   Thu May 21 18:18:18 2015 +0200

    Thirdparty lab: add warning
    
    Signed-off-by: Michael Opdenacker <michael.opdenacker at free-electrons.com>


>---------------------------------------------------------------

b45a9f0f76b70a056905e0b90d4fa5ff9d7aaae2
 labs/sysdev-thirdparty/sysdev-thirdparty.tex | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/labs/sysdev-thirdparty/sysdev-thirdparty.tex b/labs/sysdev-thirdparty/sysdev-thirdparty.tex
index c596589..fee0c65 100644
--- a/labs/sysdev-thirdparty/sysdev-thirdparty.tex
+++ b/labs/sysdev-thirdparty/sysdev-thirdparty.tex
@@ -563,6 +563,10 @@ your board, with the headset provided by your instructor plugged
 in. You will need to add the missing libraries from the toolchain
 install directory.
 
+{\bf Caution}: don't copy the \code{dmix.conf} file. \code{speaker-test}
+will tell you that it cannot find this file, but it won't work if you
+copy this file from the staging area.
+
 The sound you get will be mainly noise (as what you would get by
 running \code{speaker-test} on your PCs). At least, sound output is
 showing some signs of life! It will get much better when we play