Default [Q] Problems when calling after conversion from F180L to E975

I recently bought an Optimus G (Korean Model F180L) and followed this guide : (symbianize) /showthread.php?t=1103182 * to convert it to the E975.

I used the NEU/EUROPE OPEN kdz file, and everything is working perfectly, except ONE thing; when I try to call someone, there is no ringing sound. Then when they answer, I can't hear them.

Is this a software fault? I really don't know much about this type of stuff, what should my next course of action be? Any advice would be gratefully received!

*sorry, it won't let me post the full link due to low post count