I’m using a custom version of 4.8.3 (with some NVIDIA Tech added), and it works out of the box. However, I have a slightly different problem, which (at the first look) seems to be the same:
Only SOME sounds don’t play in the packaged build, others do. In the editor however, ALL FMOD Sounds are working.
Just a little tip: In the latest FMOD version (1.06.07), you have to add the FMOD folder with your sound bank to the Content directory of the packaged build (not in the .pak files). So if your game is named “Test” and the directory you choosed to package to is named “C:\Package” then you will have something like this:
I had the same problem, and indeed, copying the FMOD folder into the Contents folder solved the issue. Odd that the packager doesn’t copy the files for you.
But at least, it’s solved now. That’s a huge relief.