iPhone 4s, error 2001, needing new dock connector?

Hello, I have an iPhone 4s which has been stuck in the boot loop when connected to iTunes, and is giving me error 2001. The same goes while being plugged into a wall charger with an original iPhone 4 (not 4s) cable.

The only time I can get it to boot up to the normal screen is while it's plugged into a Bose Stereo system with an iPhone docking port. While plugged in, it allows me to do mainly everything, but I notice that neither the sound (music won't play through Bose speakers), nor the wi-fi seem to work.

I've had the battery terminal/connector professionally checked, but they said it was fine. I've changed the battery twice, with no different results. I've cleaned the logic board with alcohol, also to no avail. (I've also replaced the cracked screen, while dealing with this problem, but that's kinda a different matter.)

I do wonder if it's the dock connector itself. I tried replacing it once with one from eBay, but iTunes only stopped recognizing it (probably a faulty part), so I gave up and put the original one back in.

So what do you guys think? Should I try another dock connector? Or do you think it's something else?

Thank you so much for your help! God bless you guys! :)

-Daniel