This read-write value, 4 to 20, sets the silence-suppression level for voice ports on cards other than DVC, where a higher value increases attenuation of quiet periods, lowers background noise, and reduces bandwidth use. It lets an administrator trade a slightly less natural-sounding call for lower average bandwidth consumption on the voice channel. For example, raising this object toward 20 on a bandwidth-limited link during silent portions of a call frees up capacity for other traffic sharing the link.