I'm installing a piezo under saddle pickup in my acoustic. The end pin input adapter where the 1/4 jack goes in has 2 positive lugs and 1 ground lug. The wire from my piezo pickup has two wires, a positive and a ground wire... so I solder one to the input ground and other to the positive ground. Problem is the pickuo only works when I pull the guitar chord out slightly. Is there any way around this. Do I solder the one positive wire to the two positive lugs. Or do I just purchase a mono guitar chord? Not sure what to do. Pics enclosed.