diff --git a/AV.cc b/AV.cc
index 5961f75..ba862c6 100644
--- a/AV.cc
+++ b/AV.cc
@@ -151,11 +151,12 @@ void AV::stopSound(AV::Sound * s)
 {
     SDL_mutexP(m_active_sounds_mutex);
     m_active_sounds.erase(s);
-    if (m_active_sounds.size() == 0)
+    int sz = m_active_sounds.size();
+    SDL_mutexV(m_active_sounds_mutex);
+    if (sz == 0)
     {
         SDL_PauseAudio(1);
     }
-    SDL_mutexV(m_active_sounds_mutex);
 }
 
 void AV::playCallback(Uint8 * stream, int len)
@@ -190,11 +191,12 @@ void AV::playCallback(Uint8 * stream, int len)
                 min(SHRT_MAX, stream16[i] + (int)(volume * m_sound_buffer[i]));
         }
     }
-    if (m_active_sounds.size() == 0)
+    int sz = m_active_sounds.size();
+    SDL_mutexV(m_active_sounds_mutex);
+    if (sz == 0)
     {
         SDL_PauseAudio(1);
     }
-    SDL_mutexV(m_active_sounds_mutex);
 }
 
 /******************** AV::Sound ********************/