Replying to suggestions,
-Push-time has ranged from normal 10 ms button mashing to 3 secs, no change. Plus it only fails in some game sessions.
-The dll is the correct beta 15 one. Also we have tried reinstalling TS/TARS from scratch.
-Keys I use (ctrl+123 or radio) are not mapped to anything in the simulator right now, deleted those hotkeys. And in previous betas Ctrl+123 has worked flawlessly. But ok, it seems a valid thing to try, so I will try with different ones.
Mmm TS server version wouldn't affect these things, right ? (Band switch and suddenly-no-one-hears-me-after-half-an-hour-ingame issues)