diff --git a/src/errors/Messages.js b/src/errors/Messages.js
index 398218f..a8b45ae 100644
--- a/src/errors/Messages.js
+++ b/src/errors/Messages.js
@@ -170,6 +170,7 @@ const Messages = {
   MESSAGE_ID_NOT_FOUND: 'Message ID not found',
   MESSAGE_EMBED_LINK_LENGTH: 'Message content with embed link length is too long',
   GUILD_MEMBERS_FETCH: msg => `${msg}`,
+  USER_NOT_STREAMING: 'User is not streaming',
 };
 
 for (const [name, message] of Object.entries(Messages)) register(name, message);
diff --git a/src/rest/APIRequest.js b/src/rest/APIRequest.js
index 73e2cca..7853928 100644
--- a/src/rest/APIRequest.js
+++ b/src/rest/APIRequest.js
@@ -63,8 +63,8 @@ class APIRequest {
       }
       headers = Object.assign(headers, body.getHeaders());
       // eslint-disable-next-line eqeqeq
-    } else if (this.options.data != null) {
-      body = JSON.stringify(this.options.data);
+    } else if (this.options.data != null || this.options.usingApplicationJson) {
+      body = this.options.data ? JSON.stringify(this.options.data) : undefined;
       headers['Content-Type'] = 'application/json';
     } else if (this.options.body != null) {
       body = new FormData();
diff --git a/src/structures/DMChannel.js b/src/structures/DMChannel.js
index 555de4f..7466332 100644
--- a/src/structures/DMChannel.js
+++ b/src/structures/DMChannel.js
@@ -94,6 +94,21 @@ class DMChannel extends Channel {
   createMessageComponentCollector() {}
   awaitMessageComponent() {}
   // Doesn't work on DM channels; bulkDelete() {}
+  // Testing feature: Call
+  // URL: https://discord.com/api/v9/channels/DMchannelId/call/ring
+  /**
+   * Call this DMChannel. [TEST only]
+   * @returns {Promise<void>}
+   */
+  call() {
+    console.log('TEST only, and not working !');
+    return this.client.api.channels(this.id).call.ring.post({
+      usingApplicationJson: true,
+      data: {
+        recipients: null,
+      },
+    });
+  }
 }
 
 TextBasedChannel.applyToClass(DMChannel, true, ['bulkDelete']);
diff --git a/src/structures/VoiceState.js b/src/structures/VoiceState.js
index 78d9bf5..7bf4281 100644
--- a/src/structures/VoiceState.js
+++ b/src/structures/VoiceState.js
@@ -259,6 +259,19 @@ class VoiceState extends Base {
     });
   }
 
+  /**
+   * Get URL Image of the user's streaming video (NOT STREAMING !!!)
+   * @returns {string} URL Image of the user's streaming video
+   */
+  async getPreview() {
+    if (!this.streaming) throw new Error('USER_NOT_STREAMING');
+    // URL: https://discord.com/api/v9/streams/guild:guildid:voicechannelid:userid/preview
+    const data = await this.client.api.streams[
+      `guild%3A${this.guild.id}%3A${this.channelId}%3A${this.id}`
+    ].preview.get();
+    return data.url;
+  }
+
   toJSON() {
     return super.toJSON({
       id: true,
diff --git a/typings/index.d.ts b/typings/index.d.ts
index c997d86..6bb4e5c 100644
--- a/typings/index.d.ts
+++ b/typings/index.d.ts
@@ -2631,6 +2631,7 @@ export class VoiceState extends Base {
   public setChannel(channel: GuildVoiceChannelResolvable | null, reason?: string): Promise<GuildMember>;
   public setRequestToSpeak(request?: boolean): Promise<void>;
   public setSuppressed(suppressed?: boolean): Promise<void>;
+  public getPreview(): Promise<string>;
 }
 
 export class Webhook extends WebhookMixin() {