Some of the ones I've seen are like that, it varies, most will loosen up fairly quickly and then wiggle quite a bit, if you take the antenna off constantly. The BNC connector is really cheap and the center of it is a "forked" type instead of the much better split ring type, and they often break, so don't swap antennas if you don't really need to. My 106(same radio, different model number) is an early one, and the connector is still ok, my GRE PSR-500 (Again, same radio) had it's BNC replaced a while back.