For Garmin TourGuides, the .mp3 files name must contain the word "TourGuide" for the feature to be activated. For example, the .mp3 file can be named "Wineries_US_TourGuide.mp3" or "National_Trust-UK_TourGuide.mp3". Make sure you name all corresponding .BMP, .MP3 or .WAV files the same way if you are using these files.
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