Possible Clues:

• We hear what's in the speaker - a little bird!
• Person sending a messages of fewer than 140 characters
• Speaker, one delivering a short message?
• Speaker -- one addressing the world at large
• Speaker taking to social media?
• Rather quaint short word for one messaging online?
• Someone posting on social media is quaint, taking the lead with hesitation
• 19 — 15, for example
• Speaker, one sending message
• Stereo component