Although I agree with the above posts I have to ask if your speakers are phased in correctly?
Even if the + and - are the same on both speakers they still might be out of phase. I'm not knowledgable enough to (as many others are) to explain why but I know it can happen and could be an easy fix.
Even if the + and - are the same on both speakers they still might be out of phase. I'm not knowledgable enough to (as many others are) to explain why but I know it can happen and could be an easy fix.