I've had the same issue. I've followed a dozen videos and guides/SU25T manual. Randomly weapons (rockets/bombs) will just utterly refuse to fire whether you hold down the button or not, with LA, with the laser on, with the TV locked, etc etc.
I'm also 90% of the time unable to get the TV to ground lock at any range. There seem to be some pretty serious bugs with the SU25T and the weapons/TV.