Subwoofer buldging out problem
When speakers are wired in the wrong way the will do the "pushing out" you're describing. Basically the polarities have been reversed and if kept like this over a period of time will blow the speaker. Best thing to do is to disconnect the power by the negative on the amp and take out the fuse from the power supply. Check the wires running from the amp to the subs, negative to negative and positive to positive. I know it sounds basic but many people do mix it up! I would also check to see what channels the subs have been wired into?
Best way is to have one sub from channel 1 and the other sub from channel 2 for example. Or if its a bridged 4 channel amp, have 1 sub running from channel 1&2, and the second sub running from channel 3&4 still making sure of the polarities. Again this all depending what kind of amp and sub you have.
A 4 channel (bridged) 1000W amp. 250W max per channel or 500W per 2 channels! So if you have 2 500W subs, by connecting one to a single channel will decrease subs ability due to the lack of power supplied. However by combining 2 channels you optimize the output!
Once you know all your wiring from your amp to subs are ok/good connections/good wires etc you shouldnt have to "wiggle the wires" to get it to work as this is just a bad connection. Also ensure that no 2 wires are touching. Make sure that the master volume on the amp is turned down. You dont need this to be on loud at all, in fact far from it or you'll risk damaging both the amp and subs!
Hope this helps!