Never mind, I fixed the issue.
It seems that the integration code for Wwise v2014 with UE4.5 has the following bug:
In "UE4\Engine\Source\Editor\UnrealEd\Private\Editor.cpp" line 514, the "AudiokineticTools" module is loaded by the "UEditorEngine::Init" function.
In "UE4\Engine\Source\Editor\UnrealEd\Private\Editor.cpp" line 547, the "LevelEditor" module is loaded by the "UEditorEngine::Init" function.
In "UE4\Engine\Source\Developer\AudiokineticTools\Private\AudiokineticToolsModule.cpp" line 36, the "LevelEditor" module is required to have been loaded to add the "Generate SoundBanks" item by the "FAudiokineticToolsModule::StartupModule" function.
However, the "LevelEditor" module has not yet been loaded when the "FAudiokineticToolsModule::StartupModule" function executes.
Therefore, the "Generate SoundBanks" item is not added by the "FAudiokineticToolsModule::StartupModule" function.