My samsung vibrant signal has been fluctuating and so i decided to insert an external antenna to the port in the back. The signal is perfect when the external antenna is connected but now the phone does not detect any mobile signal without the antenna, at all. If I unplug the antenna, the phone loses any connection it has. Whats going on and how do i fix it?! I bought this brand new from third party so taking it to T-mobile will not be possible, i think.