I have had multiple times the exact problem.
I play just fine and dandy a pantheon multiplayer game, then suddenly my whole client crashes, dosnt send error message, dosnt give a debug screen like it used to in some cases. It simply dies, I lose a victory/favourpoints and participation in the game I just were in and thats about it.
For me it usually dosnt seem to happen in the beginning of a pantheon multiplayer but somewhere in mid/late game, so it might be tied to something like memory is flooding and client just dies or... something. honestly the code/servers are stilly you know pretty much borked...
Actually bit editing this: I have today played perhaps letsay three to four pantheon games I actually got in. All of them crashed like that, looks like whatever folks been doing it seems to been gotten worse. At least yesterday I could complete actual matches. I dont get much joy for interface not lagging like hell and back, but instead games you join all crash in halfway.
