Command - /ChanServ DEVOICE
Usage   - /ChanServ DEVOICE <#channel> [nick]
This command devoices (MODE -v) a nick on a channel.
If the nick parameter isn't used your current nick will be used.
Note: VOPs can only devoice themself.
Note: You can't devoice users with higher access than you.
Note: You need AOP or higher access on the channel to use this command on other people.
Example(s):
/ChanServ DEVOICE #kobi Kobi_S