diff -up chromium-42.0.2298.0/media/base/audio_decoder_config.h.ac3-dts chromium-42.0.2298.0/media/base/audio_decoder_config.h
--- chromium-42.0.2298.0/media/base/audio_decoder_config.h.ac3-dts	2015-02-12 22:25:55.393519941 +0100
+++ chromium-42.0.2298.0/media/base/audio_decoder_config.h	2015-02-12 22:27:48.549450295 +0100
@@ -37,13 +37,15 @@ enum AudioCodec {
   // kCodecEAC3 = 13,
   kCodecPCM_ALAW = 14,
   kCodecALAC = 15,
+  kCodecAC3 = 16,
+  kCodecDTS = 17,
   // DO NOT ADD RANDOM AUDIO CODECS!
   //
   // The only acceptable time to add a new codec is if there is production code
   // that uses said codec in the same CL.
 
   // Must always be equal to the largest entry ever logged.
-  kAudioCodecMax = kCodecALAC,
+  kAudioCodecMax = kCodecDTS,
 };
 
 // TODO(dalecurtis): FFmpeg API uses |bytes_per_channel| instead of
diff -up chromium-42.0.2298.0/media/ffmpeg/ffmpeg_common.cc.ac3-dts chromium-42.0.2298.0/media/ffmpeg/ffmpeg_common.cc
--- chromium-42.0.2298.0/media/ffmpeg/ffmpeg_common.cc.ac3-dts	2015-02-08 00:28:04.000000000 +0100
+++ chromium-42.0.2298.0/media/ffmpeg/ffmpeg_common.cc	2015-02-12 22:27:22.520927957 +0100
@@ -94,6 +94,10 @@ static AudioCodec CodecIDToAudioCodec(AV
       return kCodecOpus;
     case AV_CODEC_ID_ALAC:
       return kCodecALAC;
+    case AV_CODEC_ID_AC3:
+      return kCodecAC3;
+    case AV_CODEC_ID_DTS:
+      return kCodecDTS;
     default:
       DVLOG(1) << "Unknown audio CodecID: " << codec_id;
   }
@@ -143,6 +147,10 @@ static AVCodecID AudioCodecToCodecID(Aud
       return AV_CODEC_ID_PCM_MULAW;
     case kCodecOpus:
       return AV_CODEC_ID_OPUS;
+    case kCodecAC3:
+      return AV_CODEC_ID_AC3;
+    case kCodecDTS:
+      return AV_CODEC_ID_DTS;
     default:
       DVLOG(1) << "Unknown AudioCodec: " << audio_codec;
   }
--- chromium-46.0.2486.0/media/base/audio_decoder_config.cc.ac3dts	2015-08-17 21:07:42.000000000 +0200
+++ chromium-46.0.2486.0/media/base/audio_decoder_config.cc	2015-08-24 23:08:43.706692027 +0200
@@ -150,6 +150,10 @@
       return "opus";
     case kCodecALAC:
       return "alac";
+    case kCodecAC3:
+      return "ac3";
+    case kCodecDTS:
+      return "dts";
   }
   NOTREACHED();
   return "";