Green greasy oil on mini-usb port charger!?

[tkdghk0831]

I searched everywhere about this issue,
and it seemed to be unusual thing to happen..

I have 3 chargers(including the USB cable). One that came with my current Thunderbolt, one from the LG Ally I used to have,
And one from the featured phone I used to have years ago.
I use both of them now.

This issue actually happened when I had the Ally.
From some point when I take out the phone from the charger,
either on the mini usb port on the phone and the metal part of the charger
jack is covered with some green greasy oil on it.
And with the green oil filled in mini usb port on the phone,
the oil is now transferred to other chargers I have and now
even the port of relatively brand new Thunderbolt is filled with that green thing..
At first I didn't notice it as a big deal,

but it's been quite a while and I'm worried now..

WHY AM I GETTING THAT GREEN GREASY OIL ????????????????????
AND WHAT IS THIS GREEN THING??????????


I think the first time I saw this green oil thing was from the charger I got from the featured phone.
Would the reason be that it's too old?

I'm also wondering..
Ive been hearing squeaking noise from the adapter of this wall charger whenever I plug in my phone to it.

Why is this happening?

Do I just need a new charger?

If can, how can I clean up the green mess in my TB's mini usb port???

 

[JohnnytheK]

Many transformers have oil in them, I didn't think a small phone changers were oil filled but maybe they are. If you can ID the leaking unit, don't use it and dispose of it correctly. I've been contaminated with PCB oils from old style transformers so maybe I'm a little paranoid but,,,

Also you can usually mix and match chargers but be aware of their capacities. Just because the ports fit, it doesn't automatically they should be used. I mean too much amperage as well too little can be bad for your device. (yes I know modern devices have circuitry that protects them from this, but why take a chance.)