Check the N1MM+ macro to make sure it's not "unkeying" at the end of the string. Your 6600 should be running QSK which means you should need no TX or RX commands. I think . . . I'm still learning N1MM+ after years on WriteLog.
Thanks for reply but no TX or RX commands in the macros. When I key with paddle no problem. It drops back to receive immediately. Got it...N1MM config problem....now just have to figure why I cant change bands with n1mm