Is this a known issue? Surely it is known.
I've had this happen to me a bunch of times. Seems to happen on both iOS and Android. I play on Android and some of my buds play on iOS and we've both had it, but not everybody at once.
So far it has reliably happened whenever I don't enter the Gurgox boss room with the party the first time the boss is agroed for this instance. I've come to recognise I'm bugged when there's no voice-over saying he's the intergalactic champion. If all he does is stand there while the camera pans, I know I'll never hear his roars.
Basically if I'm not part of the initial group that enters his room, I can't hear any voice-overs at all, especially Gurgox's ohko roar. This all is fine as long as the boss doesn't deagro. If he deagros and I'm not there when he's agroed again, all voice-overs break. This happens for all bosses who have voice-overs like Mynas and the Keeper, and from the first time I lose voice-overs, they stay broken until I reboot my game client.
It's not a huge deal for the rest of the bosses that have them, but not being able to hear Gurgox's roar is gamebreaking to the point of not being able to participate in the fight and having to avoid it or make my party wait.
I'm so traumatised from getting killed by Gurgox and prefer to not fight him, my friends have been calling me a coward because I avoid the fight even if my voice-overs are fine. They're pretty much right though. It's better to avoid a fight I have no chance at, so really can you blame me for being afraid of my voice-overs bugging out and therefore being afraid of Gurgox? I don't think so.
Any ETA on a fix so the voice-overs always work?