A Note on Sound
Only MP3 and OGG files can be used. We suggest encoding your audio with a sample rate of 44.1 kHz and a bit rate of at least 192 kbps. Add the MP3 as the main file for both outputs and the OGG for the alternative file. The Flash output will always use the first (Filename) option.
However, a bit rate of 192 kbps may produce too large of a file for your project. If your audio file has a large dynamic range, e.g. music, and you want to keep the integrity of the sound, it’s best to keep the 44.1 kHz sample rate. If you wish to knock the file size down a bit, try lowering the bit rate to 160 kbps, and then to 128 kbps if needed (and then to 96 kbps).
The other option is to externalize your sound file. This happens automatically for the HTML5 output. But if outputting to Flash, be sure select Externalize.
If your sound file is not dynamically wide, e.g. a button click sound, you could use a lower sample rate. Flash supports 11 kHz, 22 kHz, and 44.1 kHz. You could then lower the bit rate.