Xiaomi HongMi keeps going Out of Service

[hnt20]

I am having a major problem with my HongMi device. I am in the US using TMO. in my area, WCDMA is on 1900 Mhz. The problem is when i plug in my SIM card on Slot1 and set the device as 3G preferred, my device works on 2G and keeps going out of service all the time and takes forever to come back. However, when i set Slot1 to 2G, everything works fine.

In addition to HongMi keep going Out of Server, it does not work on TMO 3G 1900 Mhz even though HongMi supports 1900.

is there anything need to get it working on 3G on TMO, and if not, how can i fix it from going out of service all the time on 3G..

 

[pjovp]

Does this happen in every firmware?
I'm just asking because better be a software related bug than hardware.

Try this one here
http://xiaomi.eu/community/index.php?posts/194404

 

[hnt20]

Yes, it happend on 4.0 and 5.0. i tried different ROMs as well and no luck. Not sure if anyone had any luck with TMO USA using HongMi device.