I’m also experiencing the same issue in UE5.1.1. While changing the compression to “Platform Specific” worked for unreal 5.0, it does not seem to work in any 5.1.1 project. I’m not sure if the platform settings were not correctly set in the engine or what the deal is, but something seems broken. I’d love to hear if anyone has gotten Unreal 5.1.1 to successfully package a Hololens 2 project with working sound.