A soft spoken or incoherent sound.

नम्र ध्वनि

English Usage: His humhum during the meeting made it hard to concentrate.

Hindi Usage: मीटिंग के दौरान उसकी नम्र ध्वनि ने ध्यान केंद्रित करना मुश्किल बना दिया।

A sound made by a person, such as humming.