I am having the same issue.I have a warthog HOTAS. I just reloaded the game and set the TDC slew in "Axis Commands" yesterday but when I went to use the TDC slew today it wasn't working. I check my bindings and it wasn't bound anymore. I tried to rebind but it was greyed out. Then I noticed that it now says "Vertical TDC Slew (mouse).