diff -ru SDL2-2.0.8/src/audio/emscripten/SDL_emscriptenaudio.c ../src/audio/emscripten/SDL_emscriptenaudio.c
--- SDL2-2.0.8/src/audio/emscripten/SDL_emscriptenaudio.c	2018-03-01 17:34:42.000000000 +0100
+++ ../src/audio/emscripten/SDL_emscriptenaudio.c	2018-05-26 16:09:37.263108635 +0200
@@ -246,6 +246,7 @@
     }
     SDL_zerop(this->hidden);
 #endif
+    this->hidden = (struct SDL_PrivateAudioData *)0x1;
 
     /* limit to native freq */
     this->spec.freq = EM_ASM_INT_V({ return SDL2.audioContext.sampleRate; });