Quick answer: Set the player's process_mode to Pausable (or Inherit under a pausable parent) so it halts when the tree pauses, and keep menu sounds on an Always node.
In Godot, pause behavior is per-node via process_mode. An Always node ignores pause. Setting gameplay audio to Pausable makes it stop, while menu audio stays on Always.
How to fix it
1. Set process_mode to Pausable
On the gameplay AudioStreamPlayer, set Process Mode to PROCESS_MODE_PAUSABLE so it stops processing (and playing) when get_tree().paused is true.
2. Keep menu audio on Always
Leave UI/menu audio nodes at PROCESS_MODE_ALWAYS so clicks and pause-menu music keep playing while the rest of the game is paused.
3. Check parent inheritance
If the player is set to Inherit, verify a parent is not forcing Always; the inherited mode comes from the nearest ancestor with an explicit setting.
Catching the ones you can't reproduce
The hardest version of this to fix is the one you can't reproduce — it only happens on a player's hardware, OS, driver, or save state, under conditions that simply aren't present on your machine. A report that says “it crashed” or “it froze” gives you nothing to act on, so the bug survives release after release while quietly costing you players.
Automatic error capture closes that gap. Each failure arrives with its full stack trace, the device and OS, the build number, and a breadcrumb trail of what the player did right before it broke, so even a failure you have never seen becomes a specific, reproducible issue. Fold identical failures into one signature ranked by how many players each hits, and your worklist sorts itself worst-first instead of arriving as a stream of vague complaints.
This is where a tool like Bugnet earns its place. Its SDK captures every Godot error automatically with the full stack trace plus device, OS, memory, build, and game-state context, folds duplicates into one grouped issue with an occurrence count, and ties each to the build it first appeared on — so you fix the problem that hurts the most players first and confirm it is gone when its signature disappears from the next release.
The errors you never hear about are the ones quietly costing you players. Visibility turns them into a worklist.