Depending on the structure of your Wwise project, the generated SoundBanks might not contain all required media files. Some media files might have to be packaged along side the SoundBanks.
To better understand, consider the following simple project:
One imported media file, beep.wav, with an associated SFX object sfx_beep.
One Event created to play the SFX, play_beep.
One SoundBank, called sb_beep. The SoundBank's only contents is the Event play_beep.
One target platform for the project, Windows.
The imported, unaltered file beep.wav is contained in the project's Originals folder. During SoundBank generation of sb_beep, Wwise processes beep.wav.
The file is converted according to the Conversion Settings. The converted file is stored in the project's .cache folder. Refer to Defining the Conversion Settings for Your Project for more details.
The converted file is assigned a Media ID. The Media ID is a randomly assigned 32-bit integer value. Refer to Managing Media Asset IDs for more details.
After SoundBank generation is complete, Wwise has created the file sb_beep.bnk in the configured output folder. Assume the converted file was given the Media ID 123. The file sb_beep.bnk contains the Event play_beep, which refers to media file 123.wem. Wwise will package 123.wem in sb_beep.bnk if:
If the SoundBank does not contain the media file then Wwise expects to find the file on disk. Media files on disk are expected to be found in a specific location. See sections SoundBank Output Folder Layout and Managing Loose Media Files in the Output Folder for details.