First, have you isolated/identified the problem component? To do this, switch the left and right channel speaker wires at the amp end (one end only, not at both the amp and speaker ends). If the problem stays with the same speaker, then the speaker is the problem. If the problem switches sides, then it must be upstream of the speakers (e.g., the electronic crossover).
If the problem is in the speaker, each component in the chain leading to the ESL panel could also be a problem, so you'll need to do isolation tests (substituting a component from the problem speaker with the corresponding component in the properly functioning speaker), starting with the AC polarizing plug (switch AC cords), the stepup transformer and high voltage board, and the panel itself. The latter two will require partial speaker disassembly (see the written instructions). The transformer and high voltage board are accessible through a panel underneath the woofer enclosure. The ESL panel is removed by removing the side strips, removing all the screws on both sides of the panel, and disconnecting the power and signal leads. Once you identify the defective component, you can contact InnerSound to get a replacement.
