HI THERE HELI FRIEND,THE PROBLEM MAY BE LOST MEMORY,I HAD THE SAME WITH MY 401 GYRO,YOU HAVE TO REINSTALL THE GYRO,AN GO THROUGH THE SETTINGS AGAIN,I NOW THIS IS A PAIN BUT IT WORKED FOR ME,IF IT DOES NOT WORK THE YOU GYRO HAS GOT DAMP IN IT ,OVER A LONG STORE,HOPE THIS HELPS,REGARDS HELINELLY NEIL