diff --git a/sdk/objc/api/peerconnection/RTCAudioTrack.mm b/sdk/objc/api/peerconnection/RTCAudioTrack.mm
index 3d3af34893..87deaf8aa8 100644
--- a/sdk/objc/api/peerconnection/RTCAudioTrack.mm
+++ b/sdk/objc/api/peerconnection/RTCAudioTrack.mm
@@ -151,6 +151,9 @@ void OnData(const void *audio_data,
                                   0,
                                   NULL,
                                   &buffer);
+    // format is no longer required
+    CFRelease(format);
+
     if (status != 0) {
       NSLog(@"RTCAudioTrack: Failed to allocate sample buffer");
       return;