Keep the working sound as a comparison
Confirm that a familiar system sound or another application is audible through the intended speakers. Note the physical output rather than just the volume icon. A notification from the laptop speakers does not establish that an HDMI receiver can reproduce the player’s audio.
Then play a short passage in the affected app. Keep the programme running while inspecting its mixer entry where practical, so you are looking at the active process. A player may have separate helper processes or names, so identify the entry associated with the actual playback.
Check the application volume and destination
Microsoft documents Settings → System → Sound → Volume mixer. Under Apps, confirm that the affected app is not muted and its volume is suitable. Check its Output device as well; Microsoft explicitly notes that app output can differ from the system default.
Restore a simple known route for the comparison. For example, test the app through the same speakers that already reproduced the other sound. Start quietly, because fixing a muted app after raising every upstream control can produce an unexpectedly loud result.
Inspect the player’s own audio choice
If the mixer is correct, check whether the player selected a usable audio track and whether its internal volume is muted. Compare another item in the same app. One silent programme and every programme being silent are different patterns, even though the mixer screen looks identical.
If headphones or a display were just disconnected, close and reopen the player after confirming the output. Preserve its account configuration. An app reinstall is a larger change than a route check and may not fix a per-app output choice that persists in Windows.
Escalate only the remaining scope
If every app is silent on the confirmed device, use Microsoft’s system-audio troubleshooting. If only one app remains silent across known-good items, give its publisher the version, output and mixer result. Mention whether the issue began after a device connection or update.
Avoid posting a full desktop capture with customer accounts visible. A cropped mixer view and the app’s exact error are usually better evidence. A working mixer setting cannot guarantee that every media codec or surround format is supported by the receiving equipment; those are later checks if the symptom requires them.