Single player --> Select start/resume campaign. Within 1hr the game will freeze and user needs to ALT+TAB. Sound also goes away. Once ALT+TAB, "Arma3 has stopped responding" message from windows and need to close game. Event Viewer then will have a application error with the arma3.exe crash recorded.
Has happened so far in all stages of single player campaign, as well as in multiplayer. But most consistently will happen in single player campaign.
No set recipe for reproducing it; Just load up the game and play it...