"Popping" sound after system tones and notification sounds

After system tones and notification sounds play I keep hearing a "popping" sound from the watch speaker. I hear it regardless of the volume setting. It's sometimes faint and sometimes louder, or sometimes I don't hear it at all, especially like with repeated tones such as button presses, after which you hear the pop following the last tone. Is anyone else experiencing this and maybe it just needs a firmware fix, or is it a defect In the hardware?