BT call blocking phone. Doesn’t accept # from incoming calls to screen calls

[ZOBBY1]

Hi. Not sure where the issue lies. Recently our BT call blocking phones

Have stopped screening calls successfully. Essentially what happens is that when unknown callers ring and announce their voice and press the # key the # doesn’t seem to be recognised and it keeps asking and ultimately rejecting the call. I’m on fttp with voip via Vodafone. I’m pretty sure that it used to work following my transfer to Vodafone but I can be 100%. I’ve tried resetting everything and switching everything on and off again. Workaround is disabling call screening which obviously isn’t ideal. Does anyone have any similar experiences? Can’t work out if it’s the call blocking phones which are relatively new or the landline service. Many thanks for any advice!  

[Artist360]

Hey guys. Your feedback helped me out. So the Vodafone VOIP is confirmed faulty when recognising tones. As there is no UK customer services and hitting a constant language barrier with International call centres they cant seem to understand to accept the fault. But am switching to Highland Broadband when the contract expires with Vodafone. Shame really.

[teresa-b5]

So the solution for me was for my VOIP provider (Andrews and Arnold) to change a setting at their end (something to do with DTMF) so that the legacy handset (BT8610) could "hear" the tone when the # key was pressed. Two sessions with the support team and many many other changes made and reversed along the way (some of which made it so no sound could be heard over the handset!), but persistence paid off in the end.

[JOHNSTEEL]

I am having the same issue since I switched to Vodafone from BT on Monday this week.

Basically on some incoming calls DTMF tones are not being received. On my tests I would say about 80% of the time they are not being transmitted over the VOIP audio channel. It is nothing to do with CLI which is being presented correctly as far as I can see.

On outgoing calls DTMF seems to being passed both ways OK 100% of the time. On incoming calls, outgoing DTMF is OK, it is only the incoming DTMF that is failing.

I eventually got someone in Vodafone who understood the issue and I passed over the results of my tests and a ticket has just been raised and I await feedback on that. Even though with their limited knowledge they are still trying to suggest it is the handset that is faulty.

Given it is intermittent, it suggests it depends on how the call is switched and which block of equipment and/or server it goes through, which may be incorrectly configured. I have not done any serious network engineering since I retired 25 years ago, so am not up to date on what happens in the network any longer.

[JOHNSTEEL]

Update. Vodafone closed my ticked as fixed even though it was not fixed. I called back and they opened another ticket but they seem to fail to understand the problem and I have had all sorts of strange responses blaming my handset and the BT call blocker, neither are to blame. Another strange response was because the numbers were not recognised and the hash key does not work for unrecognised numbers, but I think this is more to do with not understanding the problem. I was told the only solution was to turn off my Call Blocker. But it also means I can not access my Voicemail either or turn of my Security Alarm which also requires use of the # key, the line is useless to me without a functioning inbound # key. I have asked for this to be escalated and will pursue it until either it is resolved or I move away from Vodafone. I can't believe this has gone unnoticed by the network engineers.

I just carried out another brief test on 20 calls into my system from three different lines only on 3 occasions were the DTMF tones transmitted. So sometimes it does work, so the network is capable, but only sometimes. 

It does not appear to be an inter-network issue, I have never been able to get it to work using a Vodafone number, but have got it to work using a Virgin (O2) number.

The problem is going to be getting through to someone who actually understands the issue and is will to do something rather than just fob off with standard responses. If the VF network is not capable of reliable DTMF transmission inbound then fine, they should declare that and I will move to someone who can support it as at the moment it is a faulty product.

[Reff]

Do you have an update on this? I have been calling Vodafone, BT without anyone accepting responsibility or help. I have a BT Advanced z dect phone plugged in to the green phone input. I have 2 problems. One, as you described, where if call guardian is activated a caller not in the contact list receives a request to enter their name and press #. The unit then repeats the message again and again. I also have a problem with the answerphone. When the phone isn't answered the answerphone kicks in and takes a message but when the caller ends the call the answerphone continues recording (I guess to the end of the 30 minute maximum) and the phone is locked out. Can help with either of these problems?

[JOHNSTEEL]

I am still in discussion with this with Vodafone but at the moment not too hopeful of a solution. Their position apparently is that the phone service they provide is a basic service and that the tones sent by the # key are a 'feature' so they will not guarantee they will work. To me they should be within the basic functionality of any phone service as so many things rely on them, not only call guardian but answer machines and security systems amongst other things. If their system does not handle these then they should make that clear before anyone signs up to their service.

The reason your call guardian is not working is that it never receives any # key even though it is pressed by the caller as the Vodafone network does not transmit it most of the time, very occasionally is gets through, this points to a problem in the way the call is set up over VOIP.

I am not sure what your issue with the answer machine is, normally an answer phone stops recording when it does not hear any speech for a period of time, though I am not sure how the BT advanced Z DECT works. The answer phone in my BT call guardian DECT phone appears to work OK. It is possible that yours relies on some line condition from the exchange that is present on a copper line that is not present on a VOIP line, but I can not be sure of that.

This is from the phone manual:

• Button malfunction:

  • Check for stuck buttons: Ensure the record button is not physically stuck or partially pressed on your handset. 
  • Try a different button: If possible, experiment with using a different button to end the recording if your phone has alternative options.
• Incorrect settings:

  • Answering machine settings: Access your phone's menu to check if the answering machine is set to record for a specific duration or if it's set to record until you manually stop it. 
  • Answer delay: Adjust the "answer delay" setting to ensure the answering machine picks up the call at the right time. 
• Other potential issues:

  • Low battery: A low battery on the handset can sometimes cause erratic behavior with buttons. Try replacing the batteries. 
  • Software glitch: If possible, try performing a factory reset on your phone to clear any potential software errors.