Doesn't autoplay new messages once if last message received was an autoplayed.

ts/components/conversation/H5AudioPlayer.tsx

@@ -1,5 +1,5 @@
 // Audio Player
-import React, { useEffect, useRef } from 'react';
+import React, { useEffect, useRef, useState } from 'react';
 import H5AudioPlayer from 'react-h5-audio-player';
 import { useSelector } from 'react-redux';
 import { useTheme } from 'styled-components';
@@ -39,7 +39,7 @@ export const AudioPlayerWithEncryptedFile = (props: {
     if (
       window.inboxStore?.getState().userConfig.audioAutoplay === true &&
       props.playNextMessage &&
-      props.playableMessageIndex
+      props.playableMessageIndex !== undefined 
     ) {
       props.playNextMessage(props.playableMessageIndex);
     }

ts/components/session/conversation/SessionMessagesList.tsx

@@ -277,12 +277,15 @@ export class SessionMessagesList extends React.Component<Props, State> {
            * @param index index of message that just completed
            */
           const playNextMessage = (index: any) => {
-            const nextIndex = index - 1;
-            if (messages[nextIndex]) {
-              this.setState({
-                nextMessageToPlay: nextIndex,
-              });
+            let nextIndex: number | null = index - 1;
+
+            if (index <= 0 || messages.length < index - 1) {
+              nextIndex = null;
             }
+
+            this.setState({
+              nextMessageToPlay: nextIndex,
+            });
           };
 
           if (messageProps) {