Before starting any troubleshooting steps, make sure your laptop and external speakers/headphones are turned on and connected to each other correctly.

1. Check your audio settings in the System settings.
2. Check that the device driver is updated and that the correct device is selected.
3. Check the sound levels in the audio device settings.
4. Make sure your soundcard is enabled and that there are good connections.
5. Unplug and replug your headphones and speakers.
6. Restart your laptop to reset audio hardware settings.
7. Reinstall your audio driver.
8. If nothing else works, reset your laptop to factory settings.