When the effect / bypass switch on an FX pedal won't switch or you are receiving a weak signal from the FX pedal, the most common problem is low voltage from run down batteries. Replace and try again. We recommend you use a 9 Volt Alkaline battery. To free yourself from the battery battle you can also purchase a power supply. Your local DOD dealer can readily obtain the right power supply for your needs. The power supply reference chart will help you identify which power supply you need. If replacing the battery does not solve the problem, or you are already using a power supply, you can call the DOD Technical Service Department (See Contacts Page). They will work through the issue, and if necessary, have you send the product in to DOD, or direct you to a DOD Authorized Service Center for repair.