diff --git a/src/vgmstream.c b/src/vgmstream.c
index 27a686d5..77126b76 100644
--- a/src/vgmstream.c
+++ b/src/vgmstream.c
@@ -2444,13 +2444,13 @@ void describe_vgmstream(VGMSTREAM * vgmstream, char * desc, int length) {
 static void try_dual_file_stereo(VGMSTREAM * opened_vgmstream, STREAMFILE *streamFile, VGMSTREAM*(*init_vgmstream_function)(STREAMFILE *)) {
     /* filename search pairs for dual file stereo */
     static const char * const dfs_pairs[][2] = {
-        {"L","R"},
-        {"l","r"},
-        {"left","right"},
-        {"Left","Right"},
+        {"L","R"}, /* most common in .dsp and .vag */
+        {"l","r"}, /* same */
+        {"left","right"}, /* Freaky Flyers (GC) .adp, Velocity (PSP) .vag, Hyper Fighters (Wii) .dsp */
+        {"Left","Right"}, /* Geometry Wars: Galaxies (Wii) .dsp */
         {".V0",".V1"}, /* Homura (PS2) */
         {".L",".R"}, /* Crash Nitro Racing (PS2), Gradius V (PS2) */
-        {"_0","_1"}, /* fake for Homura/unneeded? */
+        {"_0.dsp","_1.dsp"}, /* Wario World (GC) */
         {".adpcm","_NxEncoderOut_.adpcm"}, /* Kill la Kill: IF (Switch) */ //todo can't match R>L
     };
     char new_filename[PATH_LIMIT];
@@ -2470,7 +2470,7 @@ static void try_dual_file_stereo(VGMSTREAM * opened_vgmstream, STREAMFILE *strea
     //todo other layouts work but some stereo codecs do weird things
     //if (opened_vgmstream->layout != layout_none) return;
 
-    get_streamfile_name(streamFile,new_filename,sizeof(new_filename));
+    get_streamfile_name(streamFile, new_filename, sizeof(new_filename));
     filename_len = strlen(new_filename);
     if (filename_len < 2)
         return;
@@ -2493,15 +2493,15 @@ static void try_dual_file_stereo(VGMSTREAM * opened_vgmstream, STREAMFILE *strea
             //;VGM_LOG("DFS: l=%s, r=%s\n", this_suffix,that_suffix);
 
             /* if suffix matches paste opposite suffix (+ terminator) to extension pointer, thus to new_filename */
-            if (this_suffix[0] == '.' && extension_len == this_suffix_len) { /* same extension */
-                //;VGM_LOG("DFS: same ext %s vs %s len %i\n", extension, this_suffix, this_suffix_len);
-                if (memcmp(extension,this_suffix,this_suffix_len) == 0) {
+            if (filename_len > this_suffix_len && strchr(this_suffix, '.') != NULL) { /* same suffix with extension */
+                //;VGM_LOG("DFS: suf+ext %s vs %s len %i\n", new_filename, this_suffix, this_suffix_len);
+                if (memcmp(new_filename + (filename_len - this_suffix_len), this_suffix, this_suffix_len) == 0) {
                     dfs_pair = j;
-                    memcpy (extension, that_suffix,that_suffix_len+1);
+                    memcpy (new_filename + (filename_len - this_suffix_len), that_suffix,that_suffix_len+1);
                 }
             }
-            else if (filename_len - extension_len > this_suffix_len) { /* same suffix (without extension) */
-                //;VGM_LOG("DFS: same suf %s vs %s len %i\n", extension - this_suffix_len, this_suffix, this_suffix_len);
+            else if (filename_len - extension_len > this_suffix_len) { /* same suffix without extension */
+                //;VGM_LOG("DFS: suf-ext %s vs %s len %i\n", extension - this_suffix_len, this_suffix, this_suffix_len);
                 if (memcmp(extension - this_suffix_len, this_suffix,this_suffix_len) == 0) {
                     dfs_pair = j;
                     memmove(extension + that_suffix_len - this_suffix_len, extension,extension_len+1); /* move old extension to end */
@@ -2517,7 +2517,7 @@ static void try_dual_file_stereo(VGMSTREAM * opened_vgmstream, STREAMFILE *strea
     //;VGM_LOG("DFS: match %i filename=%s\n", dfs_pair, new_filename);
 
     /* try to init other channel (new_filename now has the opposite name) */
-    dual_streamFile = open_streamfile(streamFile,new_filename);
+    dual_streamFile = open_streamfile(streamFile, new_filename);
     if (!dual_streamFile) goto fail;
 
     new_vgmstream = init_vgmstream_function(dual_streamFile); /* use the init that just worked, no other should work */