Fix T62255: Blender defaults to "OpenAL Soft" in sound settings, regardless of saved preferences

- Default device (index 0) was hard coded.
- Also fixing crash with invalid device passed to blender via -setaudio.

extern/audaspace/src/devices/DeviceManager.cpp

@@ -35,7 +35,12 @@ void DeviceManager::registerDevice(std::string name, std::shared_ptr<IDeviceFact
 
 std::shared_ptr<IDeviceFactory> DeviceManager::getDeviceFactory(std::string name)
 {
-	return m_factories[name];
+	auto it = m_factories.find(name);
+
+	if(it == m_factories.end())
+		return nullptr;
+
+	return it->second;
 }
 
 std::shared_ptr<IDeviceFactory> DeviceManager::getDefaultDeviceFactory()

source/blender/blenloader/intern/versioning_userdef.c

@@ -493,9 +493,6 @@ void BLO_version_defaults_userpref_blend(Main *bmain, UserDef *userdef)
 	if (userdef->image_draw_method == 0)
 		userdef->image_draw_method = IMAGE_DRAW_METHOD_2DTEXTURE;
 
-	// we default to the first audio device
-	userdef->audiodevice = 0;
-
 	for (bTheme *btheme = userdef->themes.first; btheme; btheme = btheme->next) {
 		do_versions_theme(userdef, btheme);
 	}