As for server fluctuations ya it happens but there is definite need for fix's on the zm server. I quit it playing on it for a few reasons.

1. No new maps. We were stuck on an endless loop of 3 maps and there was never a change.

2. Bad admins. People would purchase admin and think that they were god like and make up any rules or use there powers for there own good. I think it really needs to be established what the rules are because many admins just kick, slay, slap people for things they don't like.

3. VoteMute. Votemute should be installed on the server. There are plenty of votemute mods out there for eventscirpts and sourcemod one of them will work on the server and stop the mic spammers. I included some scripts below.

Source Mod:
http://forums.alliedmods.net/showthread.php?p=632031
http://forums.alliedmods.net/showthread.php?p=647806

Sets max time a player can hold mic down
http://forums.alliedmods.net/showthread.php?p=633905

Event Scripts:
http://addons.eventscripts.com/addons/view/votemute
http://addons.eventscripts.com/addons/view/es_votemute