She looked at the floor, and her voice lost its confidence.
This time, however, her voice had lost its earlier conviction, Instead it was asking how what they were saying could be possible.
A low voice Lost in a wilderness where none can hear!
Margaret wanted to call to him, but her voice had lost its power.
Her voice lost its heat and dropped to a near whisper.
Her voice, at least, had lost some of its terror.
He drew a breath, and his voice lost its edge.
Some may feel that his voice has lost weight as well, and the lower register does seem less powerful.
When he spoke again, his voice had lost some of its strength.
Her voice lost its power and she stared down at the floor.