You may be experiencing any of these issues:

• Top speaker only works while on phone calls
• Ringtones, notifications, and media audio only play from the bottom speaker
• Stereo audio is not working
• It looks like there is something covering part of the speaker underneath the plate

This may be normal behavior for your device.

• Some HTC Desire devices do not have stereo audio or Boomsound enhancements; the top speaker is used for standard in-call audio, while the bottom speaker is used for speakerphone and media.
• If the top speaker works while on calls but not with other audio, this may be the correct performance for your device's configuration.

If the top speaker does not function while on a call, follow these steps.

1. Ensure the speaker grill is uncovered and is not being blocked by cases, screen protectors, or debris.
   On some devices such as the HTC One (M8), the area under the speaker plates may appear partially blocked on the right side when observed closely. This is due to the fact that the physical speaker wells do not extend the full width of the device; the speaker is actually not blocked. 
2. Test the audio by dialing *#*#DIAG#*#* (*#*#3424#*#*) from the dialer.
   See How to use the Diagnostic Tool, to check audio performance.
3. If the top speaker is able to play the test sound, reboot the device and ensure all applications have been updated to the latest version.
4. If the issue persists, uninstall any third-party applications or perform a factory data reset; see How to factory data reset your device.