How do I revert my OS back to a previous version?

[Mos Sincere]

So basically when Developer Preview came out a few months ago I used it to update to GRD3, however I've had an issue that the microphone only works when I'm on the actual phone. It doesn't work on loud speak, voice commands, skype or video recording. I tried a factory reset but it kept me on the same OS version. I was being patient hoping that when an official update came my L925 would get the drivers needed from Nokia, however now I've updated to Nokia Black I still have the same issue.

What I wanted to try and do is go back to the official GRD2 and then from there update back to Nokia Black with the hope that all issues will be resolved. How do I do this? Is it also possible to do without having to reinstall all my apps and data?

Any advice would be really helpful.

 

[Memitim]

You can't.

I also had my 925 on the preview and it's on Black now and I don't have any issues with using the mic on loud speaker.

Your device might be faulty

 

[Mos Sincere]

You can't.

I also had my 925 on the preview and it's on Black now and I don't have any issues with using the mic on loud speaker.

Your device might be faulty

You sure, I know I've seen people talking about it before? I didn't have any issues before I updated to GRD3 so it's not the device..

 

[pedrodg28]

You would need to flash a country variant rom with nokia software updater for retail