has been muffling

• present perfect progressive

  present perfect progressive

  Used to describe an action that began in the past, has continued continuously, and is still in progress.

  of muffle (3rd person singular).
  muffle

  verb (used with object)

  to wrap with something to deaden or prevent sound.

Related Words

• dampen
• deaden
• envelop
• hush
• mute
• muzzle
• soft pedal
• squelch
• stifle
• subdue
• tone down