Won't Dock, Functioning Home Button, Jailbroken, Poor Call Quality

In short I have a 3G phone that I recently replaced the dock connector in due to a non-functioning home button and docking issues. Replaced the part and phone worked fine, now it's come back and it will not sync at all, battery indicator seems to stay fixed - but doesn't seem to die either. Home button retained functionality though.

Is this due to the phone still being on 3.1.3?? It's jail-broken so I was/am hesitant to restore. I've tried a few known good connectors and even swapped boards between phones.

I'm not entirely familiar with pwnage tools, but would i be able to create an ipsw that maintains it's unlockable baseband?

Thanks in advance