Regarding your problems: always work from small to big. Nine times out of ten, setup is to blame.
Two things to be careful of: First, like you said, your speaker terminals could be loose, or your connections are loose. You definitely need larger wires. Obviously, you don't have screw down terminals on your speakers, so if you want your wires to be secure, you need to either soldier, or if you're feeling half-a$$ed, find speaker circlips @ radioshack and use electrical tape.
Second, depending on how you're wiggling the wires, the amp could be going into protect mode eg. the speaker wires are grounding out somehow--however, it's most likely the first problem.
The best/easiest/cheapest way to increase the performance and reliability of your amp is using better wires. The easier current flows, the less your amp works for better sound.
I think, I tinker, I play around, I build.
'99 Contour
W Ztc, ATX, HID Fog, mesh, A6, B LED, Big 3, Alpine cda-9827, Memphis lvs12 1200w, Alpine 1241, 4xInf K 6x8, Xfire 400/4, 7.2 LCD, glv box "xbox jack" mod, interior horn alarm mod
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