If you use the plane in another arena the settings from there take over.
Not sure if that is what you experience but i use my favorites often in duelling arena with no ammo and 25% fuel, then that loadout is set next time i select them in MA. Are you sure you didnt change the loadout in another arena?
Other than that the host connection lost was a common problem on an old version... maybe it is back but i doubt it. Did you somehow manage to play with a version NOT bein the newest? i think it should be 2.01 patch 6.
Do you use preload textures in system or preload in video or both?
The old problem was that with the preloading the preload would take a while and the host would think you timed out because the game didnt react meanwhile.
Do you have the problem when you are not preloading them too?
Maybe the time for preloading takes longer now and it has to be fixed again by hitech?