As others have reported, I upgraded to fibre a few weeks ago and after an initial honeymoon, I've started to suffer from Intermittent Sync error notices and service dislocation. There's nothing wrong with my internal wiring, and I suspect the router is fine as well - this seems to me to be a network issue. Please can Talk Talk look at this urgently as my tolerance for this is going to be very low - if the service is not reliable then I will simply terminate the contract on the grounds that you are not supplying a fit for purpose service.
Any advice also welcome from the Community.
(Talk Talk - my phone number is in my profile)