Wi-Fi Calling keeps cutting out

[Applerod2]

Here are the facts first:

1) I live in an area with mediocre Verizon cellular coverage; (some calls complete, some fail, the rest break up.)

2) I've used a Verizon Network Extender for 4-5 years with an iPhone 4S and the results have been positive--except for the range, which is poor and restrictive (I live in an apartment and can only make/receive calls in a small zone near the Extender.) 

3) I recently upgraded to an iPhone SE, which supports Wi-Fi Calling.  I turned off the Network Extender.

4) I activated Wi-Fi Calling, which works--until the phone detects the unreliable cellular signal, switches over, and typically ends the phone call.  To try and circumvent this, I put the phone in airplane mode (cellular off) with Wi-Fi turned on.  This activates Wi-Fi Calling, which is usable... until it inexplicably cuts out during a conversation.

5) I have detected no problems with my Wi-Fi network.  My internet connection is reliable.

Question: Why might this be happening, and what should I do about it?

Any help is appreciated.

[LENNYEDGE]

do you turn off mobile data to test if it improves/ sometimes mobile and wifi compete.

[Applerod2]

I will try that; thanks.

[Weth]

Does your wifi router support the 5 GHz bands?  There is much less interference issues with these bands compared to 2.4 Ghz, especially in high density area such as apartments.

[Applerod2]

Yes.  Upon your suggestion, I tried switching my phone exclusively to the 5 GHz band.  The phone cut out again during a call.

I also tried LENNYEDGE's suggestion of turning off cellular data, and the problem persisted--though that doesn't seem surprising since I have the phone in Airplane Mode with Wi-Fi on during calls (unless I'm missing something.)

...I guess I'll go back to the Network Extender.  I'm stuck making and receiving calls from a single room with it, but at least it works.

[Weth]

What router do you have and what type of internet connection? My daughter has an SE and it works great with wifi calling

[Applerod2]

My router is a 4 or 5 year-old N600 (Belkin) -- so not cutting edge/top of the line, but so far enough for 1 person in an apartment.  My internet connection is via cable modem and reasonably fast by suburban standards (up to 25 Mbps wireless, close to 100 Mbps wired.)

I wonder if it's the router... I can't easily afford a newer, better one right now (so I would have to be sure.)

Thank you

[Weth · Accepted solution]

It is a fairly old router, but I agree, that is not enough to say it shouldn't work.

You could always go to someone else's place and check out wifi calling on their router.

Try a VOIP test on your router. Go to a website with an Internet Jitter or VOIP jitter test.

Couple sites to try are:

http://www.dslreports.com/tools/pingtest plus http://www.dslreports.com/speedtest

https://www.megapath.com/speedtestplus

Also there was 1 firmware update to your router, make sure you applied it:

Official Belkin Support Site | Play N600 Wireless Dual-Band N Router F7D9302fc v1 - Firmware (US)

[SOBEHALL]

Everyone seems to think this is an internet issue and it's not, I have a 150MB connection, I game, Skype, watch streaming movies all without issue,  but when making calls with wifi calling on it always breaks up, I can hear the end caller but they consistently have to ask me to repeat myself because it's breaking up. This is especially annoying during telephone visitation with my daughter.  Verizon and users continue to blame the wifi but I have a top end router and modem and consistently get my top speeds during tests.  They need to fix the issue and stop trying to blame someone else.

[Weth]

Remember with wifi calling, speed is not important.  What is important is latency and jitter.  You should run a specific voip test on your network. A speed test is not helpful really.