Remove bellAudioElement if it is not used. Remove extra import

src/InputHandler.ts

@@ -7,7 +7,6 @@ import { C0 } from './EscapeSequences';
 import { DEFAULT_CHARSET } from './Charsets';
 import { CharData } from './Types';
 import { CHAR_DATA_CHAR_INDEX, CHAR_DATA_WIDTH_INDEX } from './Buffer';
-import { BellSound } from './utils/Sounds';
 
 /**
  * The terminal's standard implementation of IInputHandler, this handles all

src/Terminal.ts

@@ -2301,6 +2301,8 @@ export class Terminal extends EventEmitter implements ITerminal, IInputHandlingT
       this.bellAudioElement.setAttribute('preload', 'auto');
       this.bellAudioElement.setAttribute('src', this.options.bellSound);
       this.element.appendChild(this.bellAudioElement);
+    } else if (this.bellAudioElement) {
+      this.bellAudioElement.remove();
     }
   }
 }