I've talked to some other in game about this and this does not seem to be unique to just me. I put in a ticket and no response. Anyone else on here noticing relentless focus losing stacks while in combat, or not firing off, or gaining stacks and you hear the sound effect that its ready, only to see its not and it now has no stacks? It's extremely unreliable at the moment. I see it mostly happen in PvP.