I have the same problem. I haven't used the F-16 since the last two updates, but it was working fine last time I used it. Two days ago I decided to fly the F-16 and had the same problem, mainly rolling left and strange pitch movements in a nose high attitude. I checked my joystick (TM Warthog), config and mission file.
I tested the joystick with other planes, no problem. I tried another joystick, same problem (with the F-16). I also have the stable version so I tested the F-16 in both DCS stable and OB, same joystick, same joystick config, same mission: default Nevada free flight in the "instant action". No icing, warm temperature. No problems in the stable version, only in the open beta.
The plane rolls left. With significant right trim I can stop it, but the when I try to roll left the plane momentarily rolls right before rolling left. With a nose high attitude, full power, over 400 kts, the nose drops aggressively and rolls left. It stabilizes in a nose low left bank attitude, while flight controls are neutral. It is unfortunately unusable right now.
I can't attach a track file they are always too large, any tip on how I should do it?
Cheers