At the moment I have not been able to do a factory reset on my 6500 I have tried the power button for 5 sec but it always goes in to calibrate mode, tried recycling the DC power before switching on also. Want to reset as with new software update it won't connect.
With the radio powered off, press and hold down the “OK” button on the front panel of the radio. Momentarily press and release the power button to power on the radio. Continue holding in the OK button until the front display counts down to 0, the power LED starts flashing white and the “CALIBRATING...” message is displayed, then release the OK button. Allow the radio to continue booting normally.
The callsign fields are not reset with a factory reset, along with some other radio specific data. Only the profiles, persistence and waveforms are reset.
From your description, it sounds like the factory reset is working properly.