Not sure what is up but a friend is having the same issue. His does the same exact thing you described. He also has the DA-50. I let him test with my DA-85 ignition and it works flawlessly. He sent the ignition back to DA and got it back with a note saying it tested out fine. He reinstalled it and the same thing. He is using a 5 cell NiMh pack as suggested by DA. Dang thing quits when it wants to. I wonder if DA tested it in a vibrating craft or on a bench.....

Kevin