I managed to play a bit on my Steam Deck and didn't have the audio issue, but I don't want to have to play this game on a small screen. I jumped back onto it on Steam via my PC further down the story and was able to play a bit on there as well, but I've noticed the audio becomes crackly/robotic again whenever there is rain in the game
At the start with Varric the audio issues were really bad on PC and it was heavily raining, and now I'm having the problem again in Arlathan Forest while there is light rain. But it does happen sporadically even without the rain, so maybe it's something to do with ambience or environmental sound effects in general?