Test fixing audio issue on first spawn

Author: AlejandroAlvarezMelucciDCL

Explorer/Assets/DCL/Audio/AudioMixerVolumesController.cs

@@ -20,6 +20,7 @@ public class AudioMixerVolumesController
         private readonly AudioMixer audioMixer;
         private readonly string[] allExposedParams;
         private readonly Dictionary<string, float> originalVolumes = new ();
+        private readonly HashSet<string> mutedGroups = new ();
 
         public AudioMixerVolumesController(AudioMixer audioMixer)
         {
@@ -36,8 +37,14 @@ public void MuteGroup(AudioMixerExposedParam groupParam)
                 if (exposedParam != groupParamString)
                     continue;
 
-                audioMixer.GetFloat(groupParamString, out float originalVolume);
-                originalVolumes[groupParamString] = originalVolume;
+                // Only store the original volume if this group hasn't been muted before
+                if (!mutedGroups.Contains(groupParamString))
+                {
+                    audioMixer.GetFloat(groupParamString, out float originalVolume);
+                    originalVolumes[groupParamString] = originalVolume;
+                    mutedGroups.Add(groupParamString);
+                }
+
                 audioMixer.SetFloat(groupParamString, MUTE_VALUE);
                 break;
             }
@@ -52,7 +59,11 @@ public void UnmuteGroup(AudioMixerExposedParam groupParam)
                 if (exposedParam != groupParamString)
                     continue;
 
-                audioMixer.SetFloat(groupParamString, originalVolumes[groupParamString]);
+                if (mutedGroups.Contains(groupParamString))
+                {
+                    audioMixer.SetFloat(groupParamString, originalVolumes[groupParamString]);
+                    mutedGroups.Remove(groupParamString);
+                }
                 break;
             }
         }