diff --git a/html5/verto/js/src/jquery.jsonrpcclient.js b/html5/verto/js/src/jquery.jsonrpcclient.js
index 5beb85fc50..4b0b71019e 100644
--- a/html5/verto/js/src/jquery.jsonrpcclient.js
+++ b/html5/verto/js/src/jquery.jsonrpcclient.js
@@ -429,8 +429,14 @@
 		var down_kps = (((this.speedBytes * 8) / (this.down_dur / 1000)) / 1024).toFixed(0);
 		
 		console.info("Speed Test: Up: " + up_kps + " Down: " + down_kps);
-		this.speedCB(event, { upDur: this.up_dur, downDur: this.down_dur, upKPS: up_kps, downKPS: down_kps });
+		var cb = this.speedCB;
 		this.speedCB = null;
+		cb(event, {
+			upDur: this.up_dur,
+			downDur: this.down_dur,
+			upKPS: up_kps,
+			downKPS: down_kps
+		});
 	    }
 	    
 	    return;