For starters: I haven't figured out exactly how to replicate it, but it seems to show up relatively consistently after firing an AGM-65D or F (the D is still the mission loadout in the AGM-65 Practice mission). I am uncertain whether or not it also happens with the E, as it's a bit more involved to retarget something.
I initially noticed it in a lightly modded client updated to 2.5.6.5590, but the issue persisted after having disabled all mods.
Issue:
After firing one or multiple AGM-65's the button commands for TDC up/down / left/right get temporarily inverted.
Steps to replicate:
Step 1: Standard AGM-65 firing procedures: A2G master mode, MA on, stores page, IRMV selected, target acquisition via DMT sensor (TV), uncage, lock via TDC action, pickle to launch AGM
Step 2: Uncage for further target acquisition -> button slew inputs get inverted.
I've had it not invert after the first maverick, only after a later launch or DMT mode switch, but in my limited testing, the above seems to be enough to trigger it.
Going to a different mode again (INS/TV/IRMV) seems to temporarily fix it.
Clip:
Obviously a bit hard to tell my inputs from video, so I'll list it via timestamps:
0:03 - AGM-65D loadout (still selected as standard mission loadout for AGM-65 Practice.miz, same occurred with AGM-65F)
0:16 - setting up for launch
1:01 - Launch 1
1:03 - Uncage 2 - normal - inputs: right-left-up-down - relock
1:09 - Launch 2
1:11 - Uncage 3 - Inverted - inputs: right-left-right-left-up-down-up-down