This a hassle free guide so you don have to download a 1.5 gb file wih is he MDL firmware
After trailand error wih out the need of flashing the whole MDL Firmware what i did was flash he MDL modem only Using Odin 3.07. once on MDL I unlocked Rooting my phone and using regionlock apk thank Chainfire for his great app. I had no sound and no WIFI so i started searching for a fix but no one had a fix for the MK2 bootloader. Checked out
thread here t=2532714http://forum.xda-developers.com/show....php?t=2532714
so he says he has a stock rom which i was about to download to fix his issue but i read a little further and found out like he posted * READ POST 3 IF YOU'RE CONFUSED ABOUT KNOX, BOOTLOADERS AND BASEBANDS. * ok checked it out and found another another post http://forum.xda-developers.com/show...9&postcount=62
and was able to download only the MK2 GSM AND LTE modems i used odin to install rebooting manuely directly to the download mode after each modem install after installing the LTE modem I reboot guess what i got wifi calls are working and most of all i got sound plus the Unlock Stuck so i kinda happy i figured this out and i can help anyone with this well makes me feel even better. Thanks to
this my friend will hopefully give you and unlock for your S4 M919.
1. Download MDL modems and flash with odin http://forum.xda-developers.com/show....php?t=2282342
2.Root M919 4.3 wih any working root *you will Trigger KNOX* http://download.chainfire.eu/328/CF-...mo-sghm919.zip
3. Download and install RegionLock Away 1.3 apk install give SU permision follow he steps you might have to restart a couple of times
4.Download and flash GSM and LTE modems wih out going directly o download mode after gsm modem flash to flash LTE right after that.
5.Reboot and Enjoy!!