diff --git a/lib/client.js b/lib/client.js
index a1ada870b..169872dff 100644
--- a/lib/client.js
+++ b/lib/client.js
@@ -2320,7 +2320,7 @@ MatrixClient.prototype.peekInRoom = function(roomId) {
 /**
  * Stop any ongoing room peeking.
  */
-MatrixClient.prototype.stopPeeking = function(roomId) {
+MatrixClient.prototype.stopPeeking = function() {
     if (this._peekSync) {
         this._peekSync.stopPeeking();
         this._peekSync = null;