A few weeks ago I upgraded from standard broadband to medium fibre. Since the upgrade the broadband connection drops 3-4 times per week for a few hours and then eventually reconnects. During this time the Broadband light blinks periodically. I have made numerous long phone calls to talktalk and went through all the usual diagnostic troubleshooting. Eventually talktalk sent an engineer to my house and concluded that the router was faulty. Talktalk sent a replacement router however this did not resolve the issue. After more phone calls talktalk agreed to send a different router (HG635) however I received an another HG633. Unfortunately this did not resolve the problem either.
Please can you advise on how to resolve this issue.
Thanks