Each version of this integration matches a specific build of Unreal Engine 4. Here is what has changed between the 2018.1.8.6907.1293 and the 2018.1.11.6987.1381 release of the integration (in addition to upgrading to the new Unreal build).

Unreal Engine 4.19/4.20/4.21/4.22/4.23 - Wwise 2018.1.11.6987.1381

• WG-45876 Fixed: Added missing URIs from the WAAPI URI list in the Blueprint.
• WG-46662 Fixed: The loading of the init bank now happens earlier in the init process.