My auto antenna tuner suddenly does not work on 20 meters. All other bands are fine. When you try to auto tune on 20, it goes into a 1 to 2 second aborted cycle and gives a successful tune indication. But there is no power output when you click on the Tune button no matter where you move the tune power slider. Also no SWR is indicated. I have tried two different antennas with different feed lines. The two antennas worked fine till this evening. I have powered the 6700 down and disconnected the power cord several times with no resolution of the problem. I have closed and reloaded SSDR. I have tried opening and closing new slices and get same results on all slices. I usually operate digital modes (psk31 and JT65) and only run15 to 20 watts. Reception is fine on all bands including 20 meters.