Looks like they've fixed the audio cutting out on maps with the new update rolling out Dec 3rd.
Dec 3 PC Game Update Notes
-Removed the blur effect on soldiers that appeared when Commanders were using EMP attacks
-Fixed the audio bug where audio sometimes randomly dropped out while playing on certain multiplayer maps (typically Golmud Railway and Hainan Resort)
-Fixed the "one-hit kill bug" where occasionally damage from a single bullet was applied multiple times
-Fixed a common crash that would occur when exiting from the Single Player Campaign to Main Menu
-Tweaked the network and computer performance screen to show proper values. Players can now test their computer and network connection and get recommendations if they need to adjust something to improve their gameplay experience