I have sc-ak640 540 watt Panasonic stereo system that I purchased off this seller about a month ago brand new which is rare to find conserding how old it is now. Anyways I begin to notice last week that the right speaker is weak while the left is stronger and basser, I already switch the wires to see if the left and right were wrong but still no difference. Could it be a fuse? Or power transformer. The warranty at this point is pretty much useless because it's from 10 years ago. Could someone please tell me what's wrong thank you and no rude answer.