Catching that GamePix muted only the Phaser sound manager while this build used a plain tag is a sharp post-mortem — especially since the ad-break path was copied from another title and never re-heard with a real ad playing.
On the fix: when an ad starts, do you pause both the element and the Web Audio context together and only resume after the SDK's ad-end callback, or is there also a visibilitychange / pagehide guard so a tab switch mid-ad can't leave music stuck?
Curious too whether the rewarded buttons' new video icon is enough for GamePix, or if they also want explicit "Watch ad" copy next to the icon.