Sorry, you're right, I'm using the WinCE-Version.
Well, I don't know anything about Android, but perhaps this will work:
Do you can locate your settings.xml file for Navigator on your mobile?
There should be the <SCOUT>-XML Tag.
In the following XML-Tags should be something like <scout_treshold_sound> and <scout_level1_sound> (level2, level3)
Is the value inside those tags something with sounds_xx_signal.mca\alarm01.wav
If yes, can you find the sounds_xx_signal.mca - file in your mobile?
Perhaps if you put your wav-files into the same place and change the value for <scout_level(1-3)_sound> to the same path as the sounds_xx_signal.mca to your wav-file, it could work?!?
E.g.
Old or actual value:
<scout_level1_sound>\User\sounds_xx_signal.mca\alarm01.wav</scout_level1_sound>
New value:
<scout_level1_sound>\User\mySound01.wav</scout_level1_sound>
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