Are you also enduring bugs in the combat queues, with the order being messed up, and possibly an unexpected pop-up saying it's not this character's turn and you have to select another one?
It becomes more and more frequent, and I suspect a number of bugs when using stealth (sneak attacks), ambushes, and even simply the extra attacks some classes get at level 5 (in my case, the monk class). With the difficulty of the combat increasing, it makes the game frustrating at times.
I can disregard the many other bugs, but this is hard to ignore.
PS: And no, it's not due to effects preventing companions from taking their actions. A typical clue is the order in which they play, which goes back & forth in the queue, and the hourglass symbols missing for some of them.