diff -r 69cc269eec53 src/audio/SDL_audiotypecvt.c
--- a/src/audio/SDL_audiotypecvt.c	Mon Aug 19 21:23:47 2019 +0200
+++ b/src/audio/SDL_audiotypecvt.c	Mon Aug 19 21:49:56 2019 +0200
@@ -337,6 +337,7 @@
 
         src = (const Sint8 *) mmsrc;
     }
+    else { SDL_Log("Not aligned %s", __func__); } 
 
     src += 15; dst += 15;  /* adjust for any scalar finishing. */
 
@@ -398,6 +399,7 @@
 
         src = (const Uint8 *) mmsrc;
     }
+    else { SDL_Log("Not aligned %s", __func__); } 
 
     src += 15; dst += 15;  /* adjust for any scalar finishing. */
 
@@ -446,6 +448,7 @@
             i -= 8; src -= 8; dst -= 8;
         }
     }
+    else { SDL_Log("Not aligned %s", __func__); } 
 
     src += 7; dst += 7;  /* adjust for any scalar finishing. */
 
@@ -495,6 +498,7 @@
             i -= 8; src -= 8; dst -= 8;
         }
     }
+    else { SDL_Log("Not aligned %s", __func__); } 
 
     src += 7; dst += 7;  /* adjust for any scalar finishing. */
 
@@ -538,6 +542,7 @@
         }
         src = (const Sint32 *) mmsrc;
     }
+    else { SDL_Log("Not aligned %s", __func__); } 
 
     /* Finish off any leftovers with scalar operations. */
     while (i) {
@@ -590,6 +595,7 @@
         }
         dst = (Sint8 *) mmdst;
     }
+    else { SDL_Log("Not aligned %s", __func__); } 
 
     /* Finish off any leftovers with scalar operations. */
     while (i) {
@@ -650,6 +656,7 @@
         }
         dst = (Uint8 *) mmdst;
     }
+    else { SDL_Log("Not aligned %s", __func__); } 
 
     /* Finish off any leftovers with scalar operations. */
     while (i) {
@@ -708,6 +715,7 @@
         }
         dst = (Sint16 *) mmdst;
     }
+    else { SDL_Log("Not aligned %s", __func__); } 
 
     /* Finish off any leftovers with scalar operations. */
     while (i) {
@@ -774,6 +782,7 @@
         }
         dst = (Uint16 *) mmdst;
     }
+    else { SDL_Log("Not aligned %s", __func__); } 
 
     /* Finish off any leftovers with scalar operations. */
     while (i) {
@@ -888,6 +897,7 @@
 
         src = (const Sint8 *) mmsrc;
     }
+    else { SDL_Log("Not aligned %s", __func__); } 
 
     src += 15; dst += 15;  /* adjust for any scalar finishing. */
 
@@ -940,6 +950,7 @@
 
         src = (const Uint8 *) mmsrc;
     }
+    else { SDL_Log("Not aligned %s", __func__); } 
 
     src += 15; dst += 15;  /* adjust for any scalar finishing. */
 
@@ -984,6 +995,7 @@
             i -= 8; src -= 8; dst -= 8;
         }
     }
+    else { SDL_Log("Not aligned %s", __func__); } 
 
     src += 7; dst += 7;  /* adjust for any scalar finishing. */
 
@@ -1029,6 +1041,7 @@
             i -= 8; src -= 8; dst -= 8;
         }
     }
+    else { SDL_Log("Not aligned %s", __func__); } 
 
     src += 7; dst += 7;  /* adjust for any scalar finishing. */
 
@@ -1072,6 +1085,7 @@
         }
         src = (const Sint32 *) mmsrc;
     }
+    else { SDL_Log("Not aligned %s", __func__); } 
 
     /* Finish off any leftovers with scalar operations. */
     while (i) {
@@ -1126,6 +1140,7 @@
         }
         dst = (Sint8 *) mmdst;
     }
+    else { SDL_Log("Not aligned %s", __func__); } 
 
     /* Finish off any leftovers with scalar operations. */
     while (i) {
@@ -1189,6 +1204,7 @@
 
         dst = (Uint8 *) mmdst;
     }
+    else { SDL_Log("Not aligned %s", __func__); } 
 
     /* Finish off any leftovers with scalar operations. */
     while (i) {
@@ -1247,6 +1263,7 @@
         }
         dst = (Sint16 *) mmdst;
     }
+    else { SDL_Log("Not aligned %s", __func__); } 
 
     /* Finish off any leftovers with scalar operations. */
     while (i) {
@@ -1305,6 +1322,7 @@
         }
         dst = (Uint16 *) mmdst;
     }
+    else { SDL_Log("Not aligned %s", __func__); } 
 
     /* Finish off any leftovers with scalar operations. */
     while (i) {
@@ -1383,10 +1401,80 @@
 
 
 
+void prepare(SDL_AudioCVT *cvt, void *buf) 
+{
+    int i;
+    memset(cvt, 0, sizeof(SDL_AudioCVT));
+    cvt->buf = buf;
+
+
+    for (i = 0; i < 2048; i++) {
+        cvt->buf[i] = i;
+    }
+
+    cvt->len_cvt = 512;
+
+}
+
+void dump(SDL_AudioCVT *cvt, char *str) 
+{
+    int i;
+    for (i = 0; i < 2048; i++) {
+        SDL_Log("%s buf[%d] = %d", str, i, cvt->buf[i]);
+    }
+}
+
 void SDL_ChooseAudioConverters(void)
 {
     static SDL_bool converters_chosen = SDL_FALSE;
 
+
+#if 1
+
+    if (converters_chosen)
+    {
+        static int valid = 1;
+        if (valid) {
+            valid = 0;
+
+    
+            const int alignment = 128;
+
+            SDL_AudioCVT cvt;
+            SDL_AudioFormat format = 0;
+            Uint8 buffer[2048 + alignment]; 
+            Uint8 *buf = (void *)(((size_t)buffer + alignment) & ~alignment);
+
+#define valid(fntype) \
+            {   \
+                prepare(&cvt, buf);     \
+                SDL_Convert_##fntype(&cvt, format); \
+                dump(&cvt, #fntype);   \
+            }   \
+
+
+            valid(S8_to_F32);
+            valid(U8_to_F32);
+            valid(S16_to_F32);
+            valid(U16_to_F32);
+            valid(S32_to_F32);
+
+            valid(F32_to_S8);
+            valid(F32_to_U8);
+            valid(F32_to_S16);
+            valid(F32_to_U16);
+            valid(F32_to_S32);
+
+
+        }
+
+    }
+
+
+#endif
+
+
+
     if (converters_chosen) {
         return;
     }