Each version of this integration matches a specific build of Unreal Engine 4. Here is what has changed between the 2018.1.1.6727.1082 and the 2018.1.2.6762.1124 release of the integration (in addition to upgrading to the new Unreal build).

Unreal Engine 4.19/4.20 - Wwise 2018.1.2.6762.1124

• WG-37990 Fixed: (Xbox One) Crash when loading large SoundBank in a packaged game not using PAK files.
• WG-38420 Fixed: Crash when Sequencer AkAudioEvent section is garbage collected while playing.
• WG-38693 Fixed: (WAAPI) Race condition in AkAutobahn, as used in various integrations and samples.
• WG-39055 Fixed: Display issue where waveform in Sequencer sections would render over text.
• WG-39091 Fixed: Made RoomComponent and LateReverbComponent compatible with level streaming.
• WG-39097 Fixed: Removed build warnings about missing samples folder.
• WG-39115 Fixed: Obstruction refresh issue on Portals.
• WG-39170 Fixed: Invalid argument passed to UnloadBank.
• WG-39219 Fixed: WAAPI reconnection issue when Wwise Authoring is quickly restarted.
• WG-39301 Fixed: CancelEventCallbackCookie does not properly use user-supplied cookies to cancel.
• WG-39334 Re-enabled Opus codec on Android and Mac.
• WG-39393 Fixed: (Switch) Invalid State Group ID.
• WG-39604 Fixed: Added description to PostAndWaitForEndOfEvent.