diff --git a/packages/transport-commons/src/channels/channel/base.ts b/packages/transport-commons/src/channels/channel/base.ts
index 7693d3c775..464eae9caa 100644
--- a/packages/transport-commons/src/channels/channel/base.ts
+++ b/packages/transport-commons/src/channels/channel/base.ts
@@ -43,7 +43,7 @@ export class Channel extends EventEmitter {
 
   join (...connections: RealTimeConnection[]) {
     connections.forEach(connection => {
-      if (this.connections.indexOf(connection) === -1) {
+      if (connection && this.connections.indexOf(connection) === -1) {
         this.connections.push(connection);
       }
     });
diff --git a/packages/transport-commons/src/channels/channel/combined.ts b/packages/transport-commons/src/channels/channel/combined.ts
index 112e95185f..840f0a1fc9 100644
--- a/packages/transport-commons/src/channels/channel/combined.ts
+++ b/packages/transport-commons/src/channels/channel/combined.ts
@@ -48,8 +48,7 @@ export class CombinedChannel extends Channel {
   }
 
   private callChildren (method: string, connections: RealTimeConnection[]) {
-    // @ts-ignore
-    this.children.forEach(child => child[method](...connections));
+    this.children.forEach((child: any) => child[method](...connections));
     this.refresh();
 
     return this;
diff --git a/packages/transport-commons/test/channels/channel.test.ts b/packages/transport-commons/test/channels/channel.test.ts
index 93129662ab..b3c1e73d7b 100644
--- a/packages/transport-commons/test/channels/channel.test.ts
+++ b/packages/transport-commons/test/channels/channel.test.ts
@@ -181,6 +181,12 @@ describe('app.channel', () => {
       assert.strictEqual(combined.length, 2);
     });
 
+    it('does nothing when the channel is undefined (#2207)', () => {
+      const channel = app.channel('test', 'me');
+      
+      channel.join(undefined);
+    });
+
     it('.join all child channels', () => {
       const c1 = { id: 1 };
       const c2 = { id: 2 };