Still no 4g with AT&T developer rom on rm-821
Quick update on my Nokia Lumia 920, (model rm-821).
I updated my wife to the Nokia Lumia 920 on AT&T's network here in the NE USA thru their upgrade. Great 4g speed, great phone. Due to contract issues (I go thru phones like water.), I went and bought a Black International, factory unlocked Nokia Lumia 920. The 920 had a Vietnam rom, and would not connect at 4g, only 3g. In the settings, there wasn't even an option for 4g, only 2g & 3g.
Going thru the forums, I saw people were reporting using US/Canadian roms to enable 4g on International 920's (model rm-821).
Thanks to the great help from people here on the forum, I downloaded the AT&T Developers rom (For America's 920's the model is rm-820, something that I was not aware of at first.) and was able to burn it to my 920.
After completing the rom burn and setting the 920 up, I called AT&T and had them re-provision the phone for 4g. This is where AT&T pushes configuration data to the phone for network and features, etc...
The phone works great, clean fast and without all the AT&T crap that was on my wife's 920. The problem? Still no 4g. Still stuck at 3g/H+, about 2/3 of the speed that my wife gets on her 920. Now I had read that using the us roms would enable the 4g mode, but after two days now the phone is still in 3g/H+. Surprisingly, the settings now show a 4g option in networking, which I've selected, but still no 4g.
So the bottom line: Do I need to return the phone and make sure that I get a US/Canadian (model rm-820) unlocked to get 4g?
I never had this problem with other unlocked international phones on 3g. Is this strictly a 4g standards issue between the international and domestic model?
Anyone have any knowledge about this, or ideas/observations?