This study's objective is to determine if electrical stimulation can safely reduced atrial fibrillation, which is an abnormal heart rhythm that begins in the top chambers of the heart. Electrical stimulation will be delivered to the wrists or in the ear. Participation will last about 6 weeks and require 3 clinic visits. Participants will be asked to wear a heart monitor and patch to monitor the heart rate and rhythm, keep a diary to collect information on atrial fibrillation, undergo randomization (being randomly assigned, like drawing straws) and use the study device per randomization assignment. Participants are randomized in a 1:1:1 fashion to a wrist worn study device, an ear piece study device or a sham wrist worn study device. A sham device looks like the real wrist worn device but does not deliver any electrical stimulation.