How to use VoLTE (AT&T HD Voice) on Lumia 950 Dual SIM (non-AT&T version)?

Hi there! @linjian thanks for posting your question. While we are certifying non-AT&T phones for use on AT&T HD voice services, we cannot guarantee all non AT&T phones will work with this service. We will first want to update the IMEI number on your account to attempt to provision this service on your phone.

So I can further assist you, please private message me by clicking here and provide your name and a good contact number. We will reach out to you to help get this resolved.

Thanks!

Darren

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@linjian wrote:

I am using a Lumia 950 Dual SIM (from Microsoft store and unlocked, non-AT&T version) with an AT&T SIM. The carrier logo shows "LTE" and the LTE data works well. However, when I call to another AT&T iPhone 6 (which is on LTE), the carrier logo changes to "4G", and the VoLTE (HD Voice) seems not work.

I checked this page: https://www.microsoft.com/en-us/mobile/support/faq/?action=singleTopic&topic=FA143885 , and make sure that Lumia 950 Dual SIM supports VoLTE.

I checked this page: https://www.att.com/esupport/article.html#!/wireless/KM1046244 , and make sure that (1) I am in a HD Voice coverage area; (2) I am using a compatible SIM card.

I also found this page: http://developer.att.com/technical-library/apns/apn-descriptions-and-characteristics , and tried both "phone" and "nxtgenphone" as the APN.

Is it due to the AT&T restriction or my setting problem? How can I use VoLTE (AT&T HD Voice) on my non-AT&T version Lumia 950 Dual SIM?

Thanks!

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@linjian

ATT has a hard time supporting phones they dont sell.  HDvoice is one of those features.  The nexus 6p and nexus 6 can do HDvoice but att wont allow it.  I would bet this to be the case with windows phones to.  If you do get them to provision you for HDvoice please post back.

@Talmage69

There is nothing to work out ATT is only supporting enhanced LTE services on ATT branded devices right now period.  HDvoice is part of enhanced services.  This is a android and windows problem as iOS is not effected.

@GLIMMERMAN76I wouldn't say it's really a "problem" with Android and Win phones, as much as a "choice" by ATT, to not support these devices, at this time.

I think they are probably constantly re-evaluating this type of decision, to decide what the breaking-point is, where customers are likely to leave, as a result, vs. selling more branded devices at a given profit margin, but that's just my take...

It does frustrate me (not enough to leave, given the current provider landscape), to be paying for the service, but not able to use it, due to the above supposition.

There was a similar type of "transition" around Visual Voicemail, some years ago, where providers started to provision, at various rates, and across various devices/OSs.

A crystal ball would be handy here, as I struggle with this a LOT in the winters, where I'm frequently at a location where I have no service, but great WiFi. If they provisioned my Win Phone, I'd be set.

Come on AT&T and Microsoft....

There are many Nokia and Microsoft branded Windows device capable of VoLTE (HD Voice) and more advanced IMS capabilities.  It is a matter of implementation and Microsoft has dropped the ball.

AT&T please help them out and in doing so please help your Windows Phone/Windows 10 Mobile ecosystem community out at the same time...

No VOLTE on a non-branded phone. We can argue and discuss industry standards, implementation and all that until we're blue in the face but it doesn't change anything. VOLTE is not available on a non-AT&T branded device.

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@David606 wrote:

No VOLTE on a non-branded phone. We can argue and discuss industry standards, implementation and all that until we're blue in the face but it doesn't change anything. VOLTE is not available on a non-AT&T branded device.

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@David606An an iOS device is AT&T branded then?
Just curious, because this seems to contradict.

iPhones are not branded in the same manner as an Android device. This does not apply to this discussion because iOS is different. Windows Phone and Android are different.