Easiest way to unlock it is to downgrade to 4.2.2 and then run RegionLock Away. Once you're done you can upgrade again and it'll remain unlocked.
I believe the no sound has something to do with which audio inputs/outputs the phone is using. I downloaded a SIP client which had the same problem as the phone, but it had options to set the input and output, I changed them and now it works perf...
Found these scripts jikantaru and tried to run them from recovery (zip from SD) but it said they were outdated and only for 1.5 android.
Perhaps a starting point?
Do you have apps2sd installed? Search for a2sd on your phone, if...
Take the android.policy out of /system/framework in my JB 4.666 Rom &add it in to your current system/framework (deodexed) ROM. And reboot.
Sent from my Nexus 4 premium
In case anyone else wanted it, it's attached below. (copy ...