AT&T Telephones and Vonage Phone Service Incompatibilities Frustrate Business

Where old and new telephone technologies collide, consumers discover usability problems.

AT&T has developed a line of highly sophisticated multi-line office telephone products – with advanced features that give both Cisco IPT and traditional PBX phone systems a run for their money – The only problem is that this range of phones (AT&T 1040, 1070 and 1080) will not work with the Vonage phone service, which just so happens to be the most popular phone service in America for small office or SOHO installations. To cut costs, even some larger corporations have switched to Vonage, which puts owners of this advanced AT&T phone hardware in a rather awkward position.

The documented problems that users have experienced when using a Vonage connection on these phones include dropped calls on pick up, dropped calls during conversation, poor speakerphone quality, poor line quality, line echo feedback, inability to transfer calls between lines and the now infamous caller ID “double 1” problem.

Out of all the issues reported, the Caller ID “Double 1” problem is perhaps the easiest issue to demonstrate and replicate as it occurs on all AT&T phones in this range when they use Vonage long distance. The LCD screen on this AT&T phone will show a “Double 1” in front of the caller ID telephone number – in effect it’s an extra 1 introduced somewhere between the Vonage and AT&T technologies that no-one can explain. Some say it’s a Bell labs ghost that’s come back to haunt the new technologies, others describe it as a fundamental design flaw in a modern phone not supporting modern technologies. It has been reported that this fault has never been seen before on any other phone in the past, so it’s a problem unique to the 10XX range including the AT&T 1070 and 1080 devices.
Example of the AT&T “Double 1” Caller ID Error

This problem hampers normal business practices in many ways as you cannot save the number, call the number back or even edit the number to correct the problem. It does however show you who called, you just cannot do anything with that information other than write it down.
To break the problem down to its fine detail, the AT&T 1070 and 1080 phones (The 1040 does not have caller ID installed) display the Vonage caller ID with an extra 1, this means that if someone calls from “212 664 4444”, normally the caller ID display would should append a “1” and show the number as “1 212 664 4444”. But when used with the Vonage service this AT&T phone appends 2 extra “1”s, so the caller ID number displayed is “11 212 664 4444” which is useless for callback, number storage into quick dial or line transfer to another the AT&T phone in this range, nullifying half of the business value of caller ID

VOIP and IPT isn’t a new technology, so how this happened is anyone’s guess, but someone may drop the ball over at AT&T design labs. Conspiracy theorists may even claim that this design flaw was an intentional act by AT&T to steal away VOIP business from Vonage, but this cannot be true because the “Double1” problem has even been seen in AT&T’s own VOIP service [Need 2nd confirmation from AT&T to publish]
Ultimately, AT&T blames the Vonage service, Vonage blames AT&T – and the end result is that consumers are left out in the cold without a fix.

AT&T customer support did follow up to this story with a statement that the 10XX phone range including the 1040, 1070 and 1080 will not work with any VOIP solution, not just Vonage. This presumably also includes the AT&T VOIP solution that many businesses and homeowners already have, but the supervisor at the AT&T call center in Indian would not confirm that.

AT&T added that, even if VOIP is in the middle of the communication path, it doesn’t matter that the two ends are POTS they recommend that this entire range of office phones should only be used with a guaranteed POTS (Plain Old Telephone System) line end-to-end.

The reality is that in the 21st century almost all telecommunication carriers use some form of IPT or VOIP in their communication path and it’s unclear to consumers why these problems are happening, what is supported and what will actually work. Even Verizon, the harbinger of old POTS lines have been replacing them with “Phone over FIOS” Fiber, which is presumably another technology not supported by this new AT&T phone range. This significantly reduces the phone’s value in the marketplace and could potentially lead to a class action lawsuit as the ATT telephone sales website does not make any mention of the exclusion of all VOIP or IPT technologies, perhaps assuming that the buyer would already know about the phones limitations from other sources.

AT&T also stated that Vonage is partly to be blame in the caller ID problem because they are not adhering to the correct VOIP standards and instead are sending too much non-standard data down the wire that confuses the phone into thinking that there are two “1’s”

The AT&T customer support line has been instructed to not accept that there is a fault with this telephone , but to emphasize that the “Feature” of being able to see the correct number of who called you in Caller ID is not available if the customer connects to any carrier that uses any part of the phone line connection in VOIP, IPT or in the cloud.

Vonage, on the other hand blamed everything on AT&T, even though Vonage could solve the problem by removing a “1” from the leading number in the caller-id data pass-through. Vonage felt so strongly (if not arrogantly) that they were not to blame (Even though they could provide a fix by removing a 1 to correct AT&T’s error) that they refused to document the error with a tracking code on multiple occasions, even when advised that this odd decision would be included in this article – the problem is clearly affecting their users, but they chose to stay out the fray.

If the Caller ID example is anything to go by, all the other documented problems that this line of phones have with newer technology may suffer the same fate in terms of “no fixes” or “developments” to determine (or provide) resolutions.
All this for a brand new office phone that has been out less than a year.

The upshot is that consumers who purchase any product from AT&T office products must do so with the knowledge that these phones may not work properly (Or at all) when plugged into any phone line that may come into contact with newer technology like VOIP or IPT somewhere along the phone line.
Only plain old copper “end to end” phone service lines are supported on this phone range by AT&T, something that businesses and homes haven’t had for years.

Story Resources and Fact Checking:

AT&T Support Line 1 800 222 3111
Complaint Tracking Code 42633649

AT&T Telephone Sales Page:
Makes no mention of the incompatibility problems with VOIP or IPT telephone lines

AT&T Contacts
Press: Fletcher Cook –

Vonage Contacts:

Vonage Support Line: 1-866-243-4357
No complaint tracking code logged as Vonage refused to document the problem, blaming the AT&T phone chipset design and programming.

Frank Roberts

A ten year veteran of remote tech writing, Frank hasn't set foot in an office for over two years. He misses the human connection, but is thankful that he doesn't have to put up with the distractions any longer. Specializing in wired/wireless tech and mobile software, Frank has written about everything from the iPhone7 to the Timex Sinclair z81/1000. This stiff is always interesting, never boring and the writing isn't bad either.