PGXL RF Power Slider won't go past 50

I am driving my PGXL with a 6600, ver 3.8.19 software. I can't move the RF Power slider past 50 when the PGXL is enabled. Nor can I edit the number in the TX Band Settings grid. If I type a larger number, it just puts 50 back in. However, the Tune Pwr slider can be moved to a higher number like 60, and it can also be edited in the TX Band Settings grid. This happens into both a 1.2:1 SWR antenna and a 1:1 dummy load. In the radio setup window, I have the Max Power set at 100. Is there a setting that is limiting this that I am missing? I can't get full power on 6m now. Any comments would be appreciated. 73, Joel N9LQ