diff -Nurd chocolate-doom-2.1.0.orig/src/i_sdlsound.c chocolate-doom-2.1.0/src/i_sdlsound.c
--- chocolate-doom-2.1.0.orig/src/i_sdlsound.c	2014-10-22 00:23:29.000000000 -0400
+++ chocolate-doom-2.1.0/src/i_sdlsound.c	2018-02-08 13:00:06.000000000 -0500
@@ -339,6 +339,7 @@
                                    int length)
 {
     SRC_DATA src_data;
+    float *data_in;
     uint32_t i, abuf_index=0, clipped=0;
     uint32_t alen;
     int retn;
@@ -346,7 +347,8 @@
     Mix_Chunk *chunk;
 
     src_data.input_frames = length;
-    src_data.data_in = malloc(length * sizeof(float));
+    data_in = malloc(length * sizeof(float));
+    src_data.data_in = data_in;
     src_data.src_ratio = (double)mixer_freq / samplerate;
 
     // We include some extra space here in case of rounding-up.
@@ -362,7 +364,7 @@
         // Unclear whether 128 should be interpreted as "zero" or whether a
         // symmetrical range should be assumed.  The following assumes a
         // symmetrical range.
-        src_data.data_in[i] = data[i] / 127.5 - 1;
+        data_in[i] = data[i] / 127.5 - 1;
     }
 
     // Do the sound conversion
@@ -430,7 +432,7 @@
         expanded[abuf_index++] = cvtval_i;
     }
 
-    free(src_data.data_in);
+    free(data_in);
     free(src_data.data_out);
 
     if (clipped > 0)