1.   And then his voice trailed off.

2.   From time to time her voice trailed off and she became her grief, heavy as a stone.

3.   Her thin voice trailed off into thin air, leaving its faint warning of damage, dirt, even theft.

4.   His thin voice trailed off.

5.   Her voice trailed off ineffectually.

6.   His voice trailed off.

7.   The thin, dreary voice trailed away.

8.   His voice trailed to a halt.

9.   His voice trailed away, rough with apology.