We experienced the same issues when interference occurred following the 700MHz auction. After we migrated off the 700MHz mics, the problem went away. Now we have four of twelve mics in the 500MHz range and eight in the recently auctioned 600MHz range. Recently during a funeral, we had the interference occur again on a couple in the 600MHz range. I don’t know if we are going to purchase another round of mics, or simply return to more wired. Unfortunate the mics were not built programmable into another range or possible to have them flashed into another range without the necessity for total replacement.