There is definitely an underlying issue here with the wiring, most likely in the Power/Ground realm or within the RCAs. Why not post some detailed pics so we can see what is going on and how it is done so it may be a bit easier to offer solutions.
I also believe there may be some wires crossed within the drivers themselves.
I am not quite sure where the confusion is as they are clearly stated Larger is Positive on every driver.
http://www.jehnert.de/wp-content/upl...mplett_neu.png