I have been extremely happy with the balanced mic input on my 6500. I am using a PR781 Heil mic directly connected to the balanced mic input on the 6500. After seeing the 6600 at Dayton, I have place my order for the 6600. However, I did notice that the balanced mic input connector is no longer offered. A call to Flex revealed that the mic input is now a 3.5mm jack. I am told with an adapter, which Flex will now add to my order, will allow me to connect my PR781 cable. I was also told that the new input keeps the balanced input all the way to the circuit board input where one side is grounded. Is this the same circuit design on the 6500 or is the 6500 a true balanced input? If this mic input circuit has indeed changed on the 6600, are there any RF interference concerns with the new design? Will the Ver 2 code still show a balanced mic input?