I recently bought a used Sansamp BDDI V1 pedal off of reverb that was listed under "good" condition. Once I received it, I covered up the battery adapter with some electrical tape so that it wouldn't interfere with the circuit. When it came to putting the pedal on my board and powering it up with an isolated power supply, the led doesn't turn on to indicate it being on. I also tried using a 9v alkaline battery, but to no avail. Is there any way for me to fix this?