Did Olympus change your body 3 times? Is this a common issue amongst E-M1 users?
first time they replaced the rear dial, and it worked fine for a few months. second time they replaced the top unit, and it worked fine again for a few months. third time, i politely requested for a replacement. i'm unlucky maybe? other friends who got their EM1 around the same time i did haven't run into this issue at all.