Probably enabling the new audio engine!
Look in the project\config\windows\WindowsEngine.ini
It contains 1 line that enables it for the project. Copy that over to the new one.
Can also enable it on your engine, so it’s always on for all your projects.
Need to move a semicolon in \engineversion\Engine\Config\Windows\WindowsEngine.ini.
There’s a sticky thread on this forum, with details.
Edit: depending on target platform, you might want to do this in f.ex \Android\AndroidEngine.ini