diff --git a/record-and-playback/core/lib/recordandplayback/edl/audio.rb b/record-and-playback/core/lib/recordandplayback/edl/audio.rb
index 34dfa1c25812e1e7c18388fb3a7da8aa169718af..9923beb721f06e6a239cf8de2c3b21f2284cdbe2 100644
--- a/record-and-playback/core/lib/recordandplayback/edl/audio.rb
+++ b/record-and-playback/core/lib/recordandplayback/edl/audio.rb
@@ -44,10 +44,10 @@ module BigBlueButton
       def self.mixer(inputs, output_basename)
         BigBlueButton.logger.debug "Mixing audio files"
 
-        ffmpeg_cmd = [*FFMPEG]	
-        inputs.each do |input|	
-          ffmpeg_cmd += ['-i', input]	
-        end	
+        ffmpeg_cmd = [*FFMPEG]
+        inputs.each do |input|
+          ffmpeg_cmd += ['-i', input]
+        end
         ffmpeg_cmd += ['-filter_complex', "amix=inputs=#{inputs.length}"]
 
         output = "#{output_basename}.#{WF_EXT}"