I think I have found what this glitch is relating to. With the new XFAD Dragur aircraft, DO NOT CRASH into the terrain. The same thing happens when Lis' TGM camera bugs and gets locked to the terrain of where you crashed. So I tested this with Lis' TGM. I fired straight up and turned it around to crash directly into the terrain. On the first shot, the camera bugged. I tried firing it at buildings, it took a few shots, but it eventually bugged, but definitely crashing into the terrain for some reason, does not reset the camera on Lis' TGM or the XFAD. Please fix it.
I don't think it's related to ground crash for the drone because it happens on my side after being shot down by AA missile.
So far what I found for vehicle spawn issue, first spawn in vehicle at beginning of match is always ok. After this first spawn, it's about being lucky or not. either you'll be able to spawn in any vehicle without a glitch and it could happen several times, either you spawn (in any vehicle) under the ground. And if spawned under the ground, it's done until the end of the game, every other spawn will be under the ground.
About lis rocket issue, the first rocket seems ok then all other are bugged (at least on my side)
