I have a service contract with AT&T and I'm currently a customer of them. I used to have the Galaxy S4 (i747), and the usb charging port stopped working. I took it into a repair shop where they messed the whole phone up and had to give me back the phone with a whole new board in it, the only problem with the new board it's a board for i747M. I was having issues with the phone being stuck on edge - so I proceeded to unlock it again (I do not trust the work they did, and even thou I had network with my AT&T SIM Card, I had to make sure it was unlocked), I also restored the old IMEI - and after all this I was able to get out of edge.
Even thou the phone reports 4G LTE, the internet is super slow!!
I made a speed test and the speeds are at 256 download // 512 upload - WEIRD!
The new board is for i747M - I already restored the IMEI to the one the original board had, I checked my APN and everything is in order.
(Did I missed anything? other than calling the repair shop and scream at them!)
I was wondering if I flash an i747 modem (MJB to be exact, since I'm on 4.3 with MK5), will the speeds improve, or will I brick the phone?
Any help greatly appreciated, I'm desperate!