A good way to do this is to wait until Rocket League is playing the song. Attempt to move all your EWEM files to a different directory. Note which file cannot be moved. Delete the file you noted in step 1. EWEM filenames contain songs. For example, 641432000.ewem contains All I Need. 706488537.ewem contains Saviour. The WEM audio file relates to Wwise, an interactive sound engine for games. Our analysis shows the WEM file is a binary audio format from the WaveWorks engine used in games like Star Wars. We explain what this file is and what software opens it. The .WEM extension is created by Audiokinetic for audio files. We hope our site is useful for file information.
EWEM Reader