.WAV file, PCM format, 22,050Hz, 16bit, Stereo.
Anything else will not work (I believe)
.WAV file, PCM format shouldn't be a problem. (it should pretty much be the default for uncompressed audio files)
Make sure you save the file at 22,050Hz, 16bit, stereo
44,100, 16bit, stereo will not work.
22,050, 8bit, stereo will not work.
22,050, 16bit, mono will not work.
You get the idea.
The key is to use the correct settings when saving the file. How to do that will be specific to the prgram you are using. Check the program's help files.
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