Need Help WIth Options... iPhone 3GS New Bootrom

Hello There,

About a year ago a friend sent me an iPhone 3GS 8GB from the States as a gift..
But I faced a problem.

The cellphone was updated to the latest iOS.


Me knowing nothing about Jailbreaking or how it even worked.. Eventually, After a lot of reading and research found a way to Downgrade the Modem Firmware and create an iOS 6.0.1 which saves the Modem Firmware to that of which I would be able to "Hack" or "Unlock" The networks so the iPhone would work with my countries networks..

But these are the problems I am facing:

Tethered Jailbreak, Have to boot from iOS 6.0 Every time.
My sound goes away and then only Headphones would work until I reinstall the iOS and go through the whole tedious process of Jailbreaking and Unlocking it again, Which costs me a lot of money due to the bad internet I have in my country.

Please can someone help me? What are my options?

Alternative iOS? (Newer but Untethered)
Send the iPhone in to get a diagnoses and see if the Headphone Jack is faulty?

I downloaded Headphone Jack from App Store, And according to the program there is NOTHING plugged into the Apple Device (Which is, There really is nothing plugged in, But external speakers will not work)

I could use some advice please :)

Warm Regards!!

Claude