Some devices like iPad (at least some of them) don't support the M4A sound files generated by the HTML5 exporter by default.
The build 282.3 has a new option in the preferences (General tab / select the HTML5 exporter) to build MP3 files instead of M4A files if lame_enc.dll is installed in the data/runtime/flash folder.
If you want to build MP3 sounds instead of M4A :
- If the SWF exporter is installed, you have nothing else to do as it contains lame_enc.dll in data/runtime/flash. Just make sure the option above is selected.
- If the SWF exporter is not installed, you need to find and download lame_enc.dll from the Internet and copy it to the data/runtime/flash folder of CF 2.5 (for example you can find it in Please login to see this link., download the zip file for Wndows). And make sure the option above is selected.