diff --git a/src/types/index.ts b/src/types/index.ts
index fad9b5b..a7e7e82 100644
--- a/src/types/index.ts
+++ b/src/types/index.ts
@@ -6,17 +6,14 @@
  */
 
 export interface AdapterAPI {
-  load?: () => void;
-  play?: () => void;
-  pause?: () => void;
-  destroy?: () => void;
-  seek?: (time: number) => void;
-  currentTime?: () => number;
-  duration?: () => number;
-  volume?: (volume: number) => void;
-  currentVolume?: () => number;
-  muted?: () => boolean;
-  mute?: (muted?: boolean) => void;
+  load: () => void;
+  play: () => void;
+  pause: () => void;
+  destroy: () => void;
+  time: number;
+  volume: number;
+  muted: boolean;
+  readonly duration: () => number;
 }
 
 export interface PlayerConfig {