How is the connection at the moment with the old router?
When you're experiencing problems does it make any difference how close the device is to your router? How many devices in your home are currently connected to the router?
The next time you experience the poor performance could you switch off everything that connects to the router by wi-fi except one device and check to see if this makes any difference. Just want to rule out one of the devices hogging bandwidth
OK thanks. The good news is I now appear to be able to communicate with your router. Could you just let me know what devices you currently have connected to your router by wifi