diff --git a/CHANGELOG.md b/CHANGELOG.md
index d05942952..e6f4551b9 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -60,6 +60,7 @@
     Bug #4947: Player character doesn't use lip animation
     Bug #4948: Footstep sounds while levitating on ground level
     Bug #4963: Enchant skill progress is incorrect
+    Bug #4964: Multiple effect spell projectile sounds play louder than vanilla
     Bug #4965: Global light attenuation settings setup is lacking
     Bug #4969: "Miss" sound plays for any actor
     Bug #4972: Player is able to use quickkeys while disableplayerfighting is active
diff --git a/apps/openmw/mwworld/projectilemanager.cpp b/apps/openmw/mwworld/projectilemanager.cpp
index b13db3a3e..19a255d8d 100644
--- a/apps/openmw/mwworld/projectilemanager.cpp
+++ b/apps/openmw/mwworld/projectilemanager.cpp
@@ -44,7 +44,7 @@
 
 namespace
 {
-    ESM::EffectList getMagicBoltData(std::vector<std::string>& projectileIDs, std::vector<std::string>& sounds, float& speed, std::string& texture, std::string& sourceName, const std::string& id)
+    ESM::EffectList getMagicBoltData(std::vector<std::string>& projectileIDs, std::set<std::string>& sounds, float& speed, std::string& texture, std::string& sourceName, const std::string& id)
     {
         const MWWorld::ESMStore& esmStore = MWBase::Environment::get().getWorld()->getStore();
         const ESM::EffectList* effects;
@@ -88,9 +88,9 @@ namespace
                 "alteration", "conjuration", "destruction", "illusion", "mysticism", "restoration"
             };
             if (!magicEffect->mBoltSound.empty())
-                sounds.push_back(magicEffect->mBoltSound);
+                sounds.emplace(magicEffect->mBoltSound);
             else
-                sounds.push_back(schools[magicEffect->mData.mSchool] + " bolt");
+                sounds.emplace(schools[magicEffect->mData.mSchool] + " bolt");
             projectileEffects.mList.push_back(*iter);
         }
         
@@ -297,9 +297,9 @@ namespace MWWorld
         createModel(state, ptr.getClass().getModel(ptr), pos, orient, true, true, lightDiffuseColor, texture);
 
         MWBase::SoundManager *sndMgr = MWBase::Environment::get().getSoundManager();
-        for (size_t it = 0; it != state.mSoundIds.size(); it++)
+        for (const std::string &soundid : state.mSoundIds)
         {
-            MWBase::Sound *sound = sndMgr->playSound3D(pos, state.mSoundIds.at(it), 1.0f, 1.0f,
+            MWBase::Sound *sound = sndMgr->playSound3D(pos, soundid, 1.0f, 1.0f,
                                                        MWSound::Type::Sfx, MWSound::PlayMode::Loop);
             if (sound)
                 state.mSounds.push_back(sound);
@@ -656,9 +656,9 @@ namespace MWWorld
             createModel(state, model, osg::Vec3f(esm.mPosition), osg::Quat(esm.mOrientation), true, true, lightDiffuseColor, texture);
 
             MWBase::SoundManager *sndMgr = MWBase::Environment::get().getSoundManager();
-            for (size_t soundIter = 0; soundIter != state.mSoundIds.size(); soundIter++)
+            for (const std::string &soundid : state.mSoundIds)
             {
-                MWBase::Sound *sound = sndMgr->playSound3D(esm.mPosition, state.mSoundIds.at(soundIter), 1.0f, 1.0f,
+                MWBase::Sound *sound = sndMgr->playSound3D(esm.mPosition, soundid, 1.0f, 1.0f,
                                                            MWSound::Type::Sfx, MWSound::PlayMode::Loop);
                 if (sound)
                     state.mSounds.push_back(sound);
diff --git a/apps/openmw/mwworld/projectilemanager.hpp b/apps/openmw/mwworld/projectilemanager.hpp
index ba2fe7a74..c7b1056b7 100644
--- a/apps/openmw/mwworld/projectilemanager.hpp
+++ b/apps/openmw/mwworld/projectilemanager.hpp
@@ -102,7 +102,7 @@ namespace MWWorld
             float mSpeed;
 
             std::vector<MWBase::Sound*> mSounds;
-            std::vector<std::string> mSoundIds;
+            std::set<std::string> mSoundIds;
         };
 
         struct ProjectileState : public State