Default Unstable reception

My problem is im geting very unstable reception. It randomly keeps dropping from HSDPA+ to no reception for a few seconds and overall i feel like my connection is worse than it was with my last phone (Galaxy Ace) and it had the same operator and connecion. I thing that I suspect is that I have replaced the bit that holds the microUSB port and I think that it also is responsible for the signal? Maybe I bought a ****ty chinese part? Or could it be something else?