The code related to t.audio.mixwithsystem=true is run before the audio module is loaded. Fixes issue #1430.

src/common/ios.h

@@ -71,7 +71,7 @@ void vibrate();
 /**
  * Enable mix mode (e.g. with background music apps) and playback with a muted device.
  **/
-void setAudioMixWithOthers(bool mixEnabled);
+bool setAudioMixWithOthers(bool mixEnabled);
 
 /**
  * Returns whether another application is playing audio.

src/common/ios.mm

@@ -347,7 +347,7 @@ void vibrate()
 	}
 }
 
-void setAudioMixWithOthers(bool mixEnabled)
+bool setAudioMixWithOthers(bool mixEnabled)
 {
 	@autoreleasepool
 	{
@@ -357,8 +357,11 @@ void setAudioMixWithOthers(bool mixEnabled)
 		if (mixEnabled)
 			category = AVAudioSessionCategoryAmbient;
 
-		if (![[AVAudioSession sharedInstance] setCategory:category error:&err])
+		bool success = [[AVAudioSession sharedInstance] setCategory:category error:&err];
+		if (!success)
 			NSLog(@"Error in AVAudioSession setCategory: %@", [err localizedDescription]);
+
+		return success;
 	}
 }
 

src/modules/audio/Audio.cpp

@@ -33,8 +33,7 @@ namespace audio
 bool Audio::setMixWithSystem(bool mix)
 {
 #ifdef LOVE_IOS
-	love::ios::setAudioMixWithOthers(mix);
-	return true;
+	return love::ios::setAudioMixWithOthers(mix);
 #else
 	LOVE_UNUSED(mix);
 	return false;

src/modules/audio/Audio.h

@@ -261,7 +261,7 @@ public:
 	 * Sets whether audio from other apps mixes with love.audio or is muted,
 	 * on supported platforms.
 	 **/
-	bool setMixWithSystem(bool mix);
+	static bool setMixWithSystem(bool mix);
 
 private:
 

src/modules/audio/wrap_Audio.cpp

@@ -526,7 +526,7 @@ int w_isEffectsSupported(lua_State *L)
 
 int w_setMixWithSystem(lua_State *L)
 {
-	luax_pushboolean(L, instance()->setMixWithSystem(luax_checkboolean(L, 1)));
+	luax_pushboolean(L, Audio::setMixWithSystem(luax_checkboolean(L, 1)));
 	return 1;
 }
 

src/modules/love/love.cpp

@@ -69,6 +69,11 @@ extern "C"
 #	include "graphics/Graphics.h"
 #endif
 
+// For love::audio::Audio::setMixWithSystem.
+#ifdef LOVE_ENABLE_AUDIO
+#	include "audio/Audio.h"
+#endif
+
 // Scripts
 #include "scripts/nogame.lua.h"
 #include "scripts/boot.lua.h"
@@ -305,6 +310,19 @@ static int w__setGammaCorrect(lua_State *L)
 	return 0;
 }
 
+static int w__setAudioMixWithSystem(lua_State *L)
+{
+	bool success = false;
+
+#ifdef LOVE_ENABLE_AUDIO
+	bool mix = love::luax_checkboolean(L, 1);
+	success = love::audio::Audio::setMixWithSystem(mix);
+#endif
+
+	love::luax_pushboolean(L, success);
+	return 1;
+}
+
 static int w_love_setDeprecationOutput(lua_State *L)
 {
 	bool enable = love::luax_checkboolean(L, 1);
@@ -362,6 +380,11 @@ int luaopen_love(lua_State *L)
 	lua_pushcfunction(L, w__setGammaCorrect);
 	lua_setfield(L, -2, "_setGammaCorrect");
 
+	// Exposed here because we need to be able to call it before the audio
+	// module is initialized.
+	lua_pushcfunction(L, w__setAudioMixWithSystem);
+	lua_setfield(L, -2, "_setAudioMixWithSystem");
+
 	lua_newtable(L);
 
 	for (int i = 0; love::VERSION_COMPATIBILITY[i] != nullptr; i++)

src/scripts/boot.lua

@@ -468,6 +468,10 @@ function love.init()
 		love._setGammaCorrect(c.gammacorrect)
 	end
 
+	if love._setAudioMixWithSystem and c.audio then
+		love._setAudioMixWithSystem(c.audio.mixwithsystem)
+	end
+
 	-- Gets desired modules.
 	for k,v in ipairs{
 		"data",
@@ -545,10 +549,6 @@ function love.init()
 		end
 	end
 
-	if love.audio then
-		love.audio.setMixWithSystem(c.audio.mixwithsystem)
-	end
-
 	-- Our first timestep, because window creation can take some time
 	if love.timer then
 		love.timer.step()

src/scripts/boot.lua.h

@@ -867,6 +867,13 @@ const unsigned char boot_lua[] =
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@@ -1002,12 +1009,6 @@ const unsigned char boot_lua[] =
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