Here's the deal: I gave a friend the S&V home tune up disk to set up his system. He says there was bass coming from the left main speaker during the sub level set up. I said, "Yes, when the system compares the level to that speaker." He says, "No, even when the sub level is playing there is bass coming from the left front." What gives? Is this a speaker issue or a receiver issue? I told him to switch speakers (mains) and see if the problem continues- assuming that if it does it's a receiver issue and if it doesn't it's a speaker issue. Any other ideas while I wait for his reply?