diff --git a/sc2/src/sc2code/libs/sound/mixsdl/decoders/decoder.c b/sc2/src/sc2code/libs/sound/mixsdl/decoders/decoder.c
index 27671bb67..87651acb0 100644
--- a/sc2/src/sc2code/libs/sound/mixsdl/decoders/decoder.c
+++ b/sc2/src/sc2code/libs/sound/mixsdl/decoders/decoder.c
@@ -82,14 +82,17 @@ static const ov_callbacks ogg_callbacks =
 	ogg_tell,
 };
 
-/* change endianness of 16bit words */
+/* change endianness of 16bit words
+ * Only works optimal when 'data' is aligned on a 32 bits boundary.
+ */
 void
 SoundDecoder_SwapWords (uint16* data, uint32 size)
 {
 	uint32 fsize = size & (~3U);
 
 	size -= fsize;
-	for (data; fsize; fsize -= 4, data += 2)
+	fsize >>= 2;
+	for (; fsize; fsize--, data += 2)
 	{
 		uint32 v = *(uint32*)data;
 		*(uint32*)data = ((v & 0x00ff00ff) << 8)
diff --git a/sc2/src/sc2code/libs/sound/mixsdl/mixer.h b/sc2/src/sc2code/libs/sound/mixsdl/mixer.h
index d73143675..45a834995 100644
--- a/sc2/src/sc2code/libs/sound/mixsdl/mixer.h
+++ b/sc2/src/sc2code/libs/sound/mixsdl/mixer.h
@@ -149,7 +149,8 @@ typedef struct _mixSDL_Buffer
 
 } mixSDL_Buffer;
 
-#define mixSDL_bufMagic 'MIXB'
+#define mixSDL_bufMagic 0x4D495842
+		// 'MIXB'
 
 typedef struct
 {
@@ -167,7 +168,8 @@ typedef struct
 
 } mixSDL_Source;
 
-#define mixSDL_srcMagic 'MIXS'
+#define mixSDL_srcMagic 0x4D495853
+		// 'MIXS'
 
 /*************************************************
  *  General interface
diff --git a/sc2/src/sc2code/libs/sound/mixsdl/trackplayer.c b/sc2/src/sc2code/libs/sound/mixsdl/trackplayer.c
index 83b6c3f24..acbf9fcb9 100644
--- a/sc2/src/sc2code/libs/sound/mixsdl/trackplayer.c
+++ b/sc2/src/sc2code/libs/sound/mixsdl/trackplayer.c
@@ -75,7 +75,7 @@ advance_track (int channel_finished)
 				PlayDecodedClip (track_clip[tcur].sample,
 						SPEECH_SOURCE, false);
 			UnlockMutex (soundSource[SPEECH_SOURCE].stream_mutex);
-			do_subtitles (~0, 0);
+			do_subtitles ((UNICODE *) ~0, 0);
 			do_subtitles (0, 0);
 		}
 		else if (channel_finished == 0)