Simple past tense and past participle of unmute.(verb)
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Use "unmuted" in a sentence
"For your sound if you have a small speaker icon on your desktop try to click on it to open it and see if it needs to be turned on or adjusted/unmuted."
"Then why not, as mentioned above, remove the startup/logon sounds completely and leave the other sounds intact and unmuted?"
"Duke held in a curse as he unmuted the phone and handed it to her."