The bull’s eye icon means there’s a balanced cable plugged in. It only comes on when the M11 is in balanced on. If you’re plugging a 3.5mm cable into the 3.5mm cable port (the one on the opposite end from the two balanced ports), then it means your M11 is stuck in balanced mode and you won’t get any sound out of your 3.5mm port. In which case, you should return your M11 and get another one. Since yours is the only M11 that’s been reported with this problem out of many thousands sold, I’d say it’s a once-off case. Return it and have it replaced.