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I have had my ProMedia speakers for a few years, and they have been fantastic, but since moving them into and back out of a storage space, they have been exhibiting a strange problem. The volume is very, very faint no matter what audio source I play from, and the volume knob does nothing (whether it is off or at full-blast, the speakers are on at the same volume, very faint). At one point I noticed that when the volume was all the way off (i.e. to the left), only the left speaker would play, and then when I turned it all the way up (to the right), only the right speaker was going, as if it were a pan knob. Has anyone else had a similar problem? I presume this is an amp issue, but it is not under warranty anymore-- do you know if there is a way to fix this without spending too much? Thank you for your help.