I need to change my routers Mac address to my previous router's.

Routers MAC addresses can not ba change. They are hard coded into the router. 

I suspect there's a different cause and solution to your ping issues.

What game are you playing where you're seeing an increase in ping?

Do you have Geo-filter configured? If so, could you share how?

Same for QoS, how do you have QoS configured?

What is the Mfr and model# of the Internet Service Providers modem/ONT the NG router is connected too?

---

XxDamienxX wrote:

Can some one help me I've had an increase in my ping lately and all the forums I read are go back to using a previous router or change your current routers Mac address to your previous router's. I have no idea how to do this do, I own a NightHawk XR500 and could use any help possible.

---

This is on page 29 of the XR500 user manual:

https://www.downloads.netgear.com/files/GDC/XR500/XR500_UM_EN.pdf 

However, I agree that the MAC address is not likely to have any bearing on this issue.  Obviously the modem connects to the XR500 hardware MAC address, so there is no need to change it.  At one time (in the dim past) there must have been situations where the ISP registered the actual MAC address of the customer equipment and replacement routers had to 'assume that identify' or they could not connect.  You are connecting.  No need to change.

The problem lies elsewhere.