topic 3G/4G & VoLTE Questions in X Series

3G/4G & VoLTE Questions

RockStar2005 — Sat, 18 Jun 2016 18:49:46 GMT

Hello all,

Some questions (Note: I have T-Mobile):

1) When the phone is on a call, instead of going to 4G (since no VoLTE, which I'm not happy about and we'll discuss in a second lol), it goes to 3G. Why is this happening?? I know it's the int'l version and all, but is there a way to alter it is so that it STAYS in 4G?? Any "flashware" that doesn't require unlocking the bootloader or rooting?? My parents have the Xperia Z1s which doesn't have VoLTE but was bought through T-Mobile, and it stays in 4G during calls, so ? lol

2) Is there any flashware to put VoLTE on this phone? I know some foreign versions of the XP have VoLTE, but apparently the int'l version does not. At least with VoLTE I'd have LTE during the call.

Thanks to anyone who thinks they can help!

Re: 3G/4G & VoLTE Questions

Uliwooly — Sat, 18 Jun 2016 18:59:35 GMT

@RockStar2005

1 That's how your carrier handle data and calls

2 No, it won't work

Re: 3G/4G & VoLTE Questions

RockStar2005 — Sat, 18 Jun 2016 19:02:57 GMT

uli,

But again, it's not. My parents are ALSO on T-Mobile (though they're phones are locked with T-Mobile and from T-Mobile, but why should that matter??), and they too do NOT have VoLTE on their phones. But their phones stay in 4G during calls. Mine switches back & forth from 3G to H+ (aka HSPA+). What gives??

Re: 3G/4G & VoLTE Questions

Uliwooly — Sat, 18 Jun 2016 19:04:57 GMT

@RockStar2005

Keep in mind that T-mobile advertised H+ as 4G, which H+ it is NOT 4G LTE, it is faster than 3G but not LTE; so that could be the issue here, that your parent's network branded phones display 4G even if it's H+.

Re: 3G/4G & VoLTE Questions

RockStar2005 — Sat, 18 Jun 2016 19:09:00 GMT

Interesting. So is H+ actually 3.5G or 4G?? lol SO confusing.

Re: 3G/4G & VoLTE Questions

Uliwooly — Sat, 18 Jun 2016 19:10:42 GMT

@RockStar2005

H+ it's 3.5G, but AT&T and T-mobile mislead people saying that H+ it's 4G, there seems to be a loophole and they took advantage of it.

Re: 3G/4G & VoLTE Questions

RockStar2005 — Sat, 18 Jun 2016 19:13:18 GMT

Ok. Weird. lol But thanks! So my phone is switching b/t 3G and 3.5G/H+ then. Great! lol

Re: 3G/4G & VoLTE Questions

Uliwooly — Sat, 18 Jun 2016 19:19:02 GMT

@RockStar2005

from 3G to H+ to LTE

Re: 3G/4G & VoLTE Questions

RockStar2005 — Sat, 18 Jun 2016 19:22:49 GMT

uli,

No.......DURING a call, it switches back & forth between 3G & H+/3.5G....... it NEVER shows LTE until I'm OFF the call, and not 'til about 10 seconds after that occurs.

Re: 3G/4G & VoLTE Questions

Uliwooly — Sat, 18 Jun 2016 19:26:44 GMT

@RockStar2005

That's a bummer, you should contact Tmobile and ask them how they handle their calls

Re: 3G/4G & VoLTE Questions

RockStar2005 — Sat, 18 Jun 2016 19:31:37 GMT

uli,

Well I've had them for over 2 years now. I know exactly how they handle the calls using THEIR LOCKED phones. But apparently there's more to it than just the VoLTE-certification, b/c my phone is no different than the T-Mo Z1s EXCEPT that it's unlocked and int'l. I may try to get their help on this, but I'm sure they'll say "blah blah blah, it's an unlocked phone, so we can only do so much...." lol F'ing Sony should've made it so the phone stays in 4G. But MAYBE it's T-Mo's fault? I dunno. I'll try them anyway cuz I know Sony Mobile won't know anything. What a mess that company is considering how amazing their phones are. Great phones, but company is run by the world's biggest dummies. lol

Re: 3G/4G & VoLTE Questions

Uliwooly — Sat, 18 Jun 2016 19:47:20 GMT

@RockStar2005

Sony doesn't have control on how a network handle the calls and/or data, think of Verizon, they can't have data and calls at the same time, AT&T does the same as T-mobile, it will disable LTE data while on calls.

Re: 3G/4G & VoLTE Questions

RockStar2005 — Sat, 18 Jun 2016 19:56:59 GMT

uli,

Well I've been told Verizon CAN do both now, but when I had them (pre-Feb 2014) they couldn't.

If the phone has VoLTE though AT&T wouldn't disable LTE. T-Mobile requires some idiotic certification by phone manufacturers in order for Band 12 (assuming that's the signal your phone is using at any given moment) to allow for LTE data AND voice during a call. AT&T does not. (Trust me, I've researched this. lol) So if my phone had VoLTE and I had AT&T, I'd get LTE no matter what, but on T-Mobile, I wouldn't unless Sony did that certification, which they didn't do, CUZ they're super dummies. lol

I may try to see if T-Mo's Tech Support ppl can help, but I seriously doubt it. At least now I know I'm getting 3G AND 3.5G/H+. lol

Re: 3G/4G & VoLTE Questions

Lord_viridis — Sun, 19 Jun 2016 08:45:00 GMT

Sony can't make the phone so it stays on 4g, it's the sim card that determines what feature gets access to what network type, and even then, the Volte depends on a certain firmware to be installed to allow volte.
Unless it's a t-mo rom, it will always revert to 3g signals during calls and reconnect to 4g when finished.

Re: 3G/4G & VoLTE Questions

RockStar2005 — Sun, 19 Jun 2016 18:03:29 GMT

Yeah. But would having the US software have any affect on keeping it in 4G vs. 3G/H+?? Or no?

Does the US firmware have VoLTE??

Re: 3G/4G & VoLTE Questions

Lord_viridis — Sun, 19 Jun 2016 19:00:33 GMT

It is network dependant and something they control.

Re: 3G/4G & VoLTE Questions

Uliwooly — Tue, 21 Jun 2016 19:17:08 GMT

@RockStar2005

No, unless T-mobile or AT&T carry this phone and they enable it.

Re: 3G/4G & VoLTE Questions

RockStar2005 — Wed, 22 Jun 2016 01:45:11 GMT

Alright thanks guys.

I called T-Mobile's Tech Support Dept. They said that since right now I don't have Band 12 (700 MHz) in my area (which I already knew)...... I only have Band 2 (1900 MHz), that's why I'm only getting 3G/H+ when I make a call. But once Band 12 gets deployed in my area (Chicago..........T-Mobile just purchased a ton of 700 MHz spectrum, which should take 3-6 months to get deployed) I should start seeing my calls occur in 4G. So prob around New Year's or sooner I should see a change.

Re: 3G/4G & VoLTE Questions

SONYDiana — Tue, 23 Aug 2016 17:51:39 GMT

4G / LTE is data only. Does not matter for voice.

Re: 3G/4G & VoLTE Questions

RockStar2005 — Tue, 23 Aug 2016 18:19:20 GMT

Yeah but VoLTE is voice over LTE, which improves the signal.

I'd like to have VoLTE for calls too, but not sure I will with this phone. If I have it 4G LTE for data WITH Band 12, then I'll be happy. I'll find out soon if this will be so or not on T-Mobile's network.