I have a several years old Surfboard SB8200 modem attached to Xfinity internet cable and using a Netgear Orbi RPR50 mesh network. All has been working fine during this time with download speeds of around 550 Mbps. Just recently (past 2 weeks) the wifi has been stopping completely for several minutes, then will start up again for a few minutes. This cycle has been happening now constantly. A speed test of the Orbi using their phone app is showing about 40 Mbps download speed, when the internet is working. The Orbi is updated to the latest firmware version. Testing of the internet done by Xfiinity’s automated system shows no issues with their signal. An Xfinity technician came out today and ran tests of the cable coming into my house. Speed test shows the cable is sending out about 1700 Mbps download. When the technician unhooked the Orbi and tested the download speed coming out of the SB8200, it showed a download speed of only 70 Mbps. The technician is suggesting that the SB8200 is defective and needs to be replaced. Can I do anything else other than replacing the SB8200?  Thanks for any feedback.