From 74ae29503605ff47099554bb0c6cd227592eab49 Mon Sep 17 00:00:00 2001
From: cosmonaut <evan@moonside.games>
Date: Thu, 29 Jun 2023 15:01:22 -0700
Subject: [PATCH] fix audio thread race condition on StaticAudio.GetInstance

---
 src/Audio/StaticSound.cs | 31 +++++++++++++++++++++++++------
 1 file changed, 25 insertions(+), 6 deletions(-)

diff --git a/src/Audio/StaticSound.cs b/src/Audio/StaticSound.cs
index d3ecd252..975af1e8 100644
--- a/src/Audio/StaticSound.cs
+++ b/src/Audio/StaticSound.cs
@@ -272,22 +272,41 @@ namespace MoonWorks.Audio
 		/// </summary>
 		public StaticSoundInstance GetInstance(bool autoFree = true)
 		{
-			if (AvailableInstances.Count == 0)
+			StaticSoundInstance instance;
+
+			lock (AvailableInstances)
 			{
-				AvailableInstances.Push(new StaticSoundInstance(Device, this));
+				if (AvailableInstances.Count == 0)
+				{
+					AvailableInstances.Push(new StaticSoundInstance(Device, this));
+				}
+
+				instance = AvailableInstances.Pop();
 			}
 
-			var instance = AvailableInstances.Pop();
 			instance.AutoFree = autoFree;
-			UsedInstances.Add(instance);
+
+			lock (UsedInstances)
+			{
+				UsedInstances.Add(instance);
+			}
+
 			return instance;
 		}
 
 		internal void FreeInstance(StaticSoundInstance instance)
 		{
 			instance.Reset();
-			UsedInstances.Remove(instance);
-			AvailableInstances.Push(instance);
+
+			lock (UsedInstances)
+			{
+				UsedInstances.Remove(instance);
+			}
+
+			lock (AvailableInstances)
+			{
+				AvailableInstances.Push(instance);
+			}
 		}
 
 		protected override unsafe void Destroy()