I am troubleshooting an issue with a user who claims delay in calls which come through a call center. Calls direct to/from the PSTN are fine. The call center for its part has recordings showing that voice received from either end of the connection is just fine. So I am left trying to get objective data on the user's experience. I have a three UCM cluster. Can I record calls with what I have or is a third party product required for this. If you could point me to a how-to if this is available - much appreciated. Thank you.