diff --git a/src/controller/buffer-controller.ts b/src/controller/buffer-controller.ts
index 334ce1221c8..bcdb23e4767 100644
--- a/src/controller/buffer-controller.ts
+++ b/src/controller/buffer-controller.ts
@@ -30,7 +30,6 @@ import { LevelDetails } from '../loader/level-details';
 
 const MediaSource = getMediaSource();
 const VIDEO_CODEC_PROFILE_REPACE = /([ha]vc.)(?:\.[^.,]+)+/;
-const AUDIO_CODEC_REGEXP = /flac|opus/gi;
 
 export default class BufferController implements ComponentAPI {
   // The level details used to determine duration, target-duration and live
@@ -257,11 +256,8 @@ export default class BufferController implements ComponentAPI {
           );
           if (currentCodec !== nextCodec) {
             let trackCodec = levelCodec || codec;
-            if (trackName.indexOf('audio') !== -1) {
-              trackCodec = trackCodec.replace(
-                AUDIO_CODEC_REGEXP,
-                getCodecCompatibleName
-              );
+            if (trackName.slice(0, 5) === 'audio') {
+              trackCodec = getCodecCompatibleName(trackCodec);
             }
             const mimeType = `${container};codecs=${trackCodec}`;
             this.appendChangeType(trackName, mimeType);
@@ -723,8 +719,8 @@ export default class BufferController implements ComponentAPI {
         // use levelCodec as first priority
         let codec = track.levelCodec || track.codec;
         if (codec) {
-          if (trackName.indexOf('audio') !== -1) {
-            codec = codec.replace(AUDIO_CODEC_REGEXP, getCodecCompatibleName);
+          if (trackName.slice(0, 5) === 'audio') {
+            codec = getCodecCompatibleName(codec);
           }
         }
         const mimeType = `${track.container};codecs=${codec}`;
diff --git a/src/controller/level-controller.ts b/src/controller/level-controller.ts
index d0b785c6581..0d513cf8c90 100644
--- a/src/controller/level-controller.ts
+++ b/src/controller/level-controller.ts
@@ -26,8 +26,6 @@ const chromeOrFirefox: boolean = /chrome|firefox/.test(
   navigator.userAgent.toLowerCase()
 );
 
-const AUDIO_CODEC_REGEXP = /flac|opus/gi;
-
 export default class LevelController extends BasePlaylistController {
   private _levels: Level[] = [];
   private _firstLevel: number = -1;
@@ -112,10 +110,7 @@ export default class LevelController extends BasePlaylistController {
       }
 
       if (levelParsed.audioCodec) {
-        levelParsed.audioCodec = levelParsed.audioCodec.replace(
-          AUDIO_CODEC_REGEXP,
-          getCodecCompatibleName
-        );
+        levelParsed.audioCodec = getCodecCompatibleName(levelParsed.audioCodec);
       }
 
       const levelKey = `${levelParsed.bitrate}-${levelParsed.attrs.RESOLUTION}-${levelParsed.attrs.CODECS}`;
diff --git a/src/utils/codecs.ts b/src/utils/codecs.ts
index 91d84a41a6f..6cf67f60ce5 100644
--- a/src/utils/codecs.ts
+++ b/src/utils/codecs.ts
@@ -118,6 +118,9 @@ function getCodecCompatibleNameLower(
   return lowerCaseCodec;
 }
 
+const AUDIO_CODEC_REGEXP = /flac|opus/i;
 export function getCodecCompatibleName(codec: string): string {
-  return getCodecCompatibleNameLower(codec.toLowerCase() as LowerCaseCodecType);
+  return codec.replace(AUDIO_CODEC_REGEXP, (m) =>
+    getCodecCompatibleNameLower(m.toLowerCase() as LowerCaseCodecType)
+  );
 }