This past few weeks I've noticed, about one time in four when I make a call, I hear the DTMF tones then it goes straight back to dial tone. This will persist for a minute or two, calls repeatedly failing, then is OK for a few hours. Then it comes back again. There is no pattern, any number is as likely as any other to fail. DSL speeds and error rates are at an all-time 'good' (ie high/low respectively), and there's no noise or other problems once connected.
My hunch is that the exchange is at fault, or even overloaded, but clearly this could also be a faulty phone. All handsets (from multiple vendors) are affected, but all my handsets are assigned to a single DECT base station, which could be the culprit. It's going to be a real pain to exclude the 'faulty phone' possibility as it means losing all my DECT extensions for the time it takes, maybe a few days or more, whilst waiting for the fault to reappear. So I was wondering if it might also be a recognised symptom of a common exchange fault, and whether i could reasonably expect BT to look for such an exchange fault, before I go to the inconvenience of it all?
I haven't spoken to BT yet as my patience ran out after after a l-o-n-g time on their call queue, but I can give it another try.
