Moto G and Sony Xperia time out on T-mobile USA cellular ? 408

Question

Ok, here is the situation.  

Four Devices all tested using the same exact SIM card from T-mobile and the same Voip.ms SIP account. ( sim cards have been updated in case that was an issue, no luck)

1. Samsung S7 -        Zoiper works on both WiFi and cellular, no issues.

2. Nexus 5x               Zoiper works on both WiFi and cellular, no issues.

3. Moto G Play          Zopier works on WiFi.  On Cellular the sip account stays registered but outgoing calls time out (408)

4. Sony Xperia X C    Zopier works on WiFi.  On Cellular the sip account stays registered but outgoing calls time out (408)

STUN has been enabled/disabled many times,  as well as rport.

** As a side note, the same time out happens with another SIP soft phone for android as well. This leads me to believe its a setting in Android System on the two devices that are timing out.

Any guesses on a solution ?

Thanks

Answer 1

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I started reviewing/changing the APN settings ...

On the devices that would not work over cellular the APN IP needed to be changed to IPv4  ( or the combo IPv4/IPv6 works as well ) Once this change is made Zoiper works as it should over cellular.

With the other devices Zoiper works fine on IPv6.

Doesn't make sense to me with 4 devices using the same SIM card,  but there you have it!

J

Comments

Ok just got a new Moto G5 Plus..... 

Zoiper works fine over WiFi. It does not work over T-mo cellular IPv6.

Now the new Moto G5 will not get data at all when I switch to IPv4. Same SiM card gets data on both IP protocols on my Nexus!  

What the heck is Moto doing with their phones to cause this  ???

Ugggh.

J