The dos of voice channel etiquette
DO fall back on the old rule of netiquette from the early days of internet forums and communities: Listen in on your new community and get a feel for how people conduct themselves before you attempt to contribute. You'll quickly figure out when it's OK to chat, when it's time to keep the channel clear and what the guild culture is for verbal roughhousing.
DO normalize your settings. Spend time before an event adjusting your settings, and ask someone else to let you know how your settings sound on their end. Make sure your mic isn't so close to your mouth that you sound like a tauren in bear form or so far away that nobody can hear you clearly.
DO feel free to chat and banter between encounters and during routine, easy play.
DO zip your lip when it's time to focus. Keep the channel clear for strategy and coordination during boss fights and during strategy briefings.
DO watch your language. Never assume that because nobody has said anything (yet) that they're cool with the blue streak you just cursed up. You're in a public social setting; conduct yourself accordingly.
DO include your name when you make a request or announcement during an encounter ("Kaed picking up adds on the right"), at least until others get to know your voice.
DO use push-to-talk if there's background noise (a barking dog, children, a television, music) in the room where you're playing.
DO use push-to-talk if you are eating at the keyboard. (Better yet: Feed your face before you sit down to play.)
DO speak up during a strategy session if you have something useful to add. If you're hesitant, shoot the raid leader a brief whisper asking if it's OK to speak up with your idea.
DO move to a private channel for individual groups or private conversations.
The don'ts of voice channel etiquette
DON'T use speakers and a separate mic instead of a headset. This causes feedback when other people speak while your mic is open -- truly a horrible experience for your teammates. Buy a headset; prices are quite reasonable today.
DON'T conduct a group or raid in the entry or "lounge" channel, where you'll be distracted by other players logging in and out. Move your event to a designated or open channel.
DON'T conduct personal or intimate conversations on an open channel that's not password-protected from anyone you wouldn't want overhearing you.
DON'T play loud music in the background or (heaven forbid) in the channel itself. Yes, we realize you probably think that sad trombone sound would be hilarious, but sound effects are something that's definitely the province of long-time guild members with an intuitive understanding of their guildmates' sense of humor.
DON'T program a song or sound effect introduction for whenever you join or leave a channel. We really don't want to hear all that in the middle of whatever we're doing when you wheel in on your chariot of flaming glory.
DON'T use language that's offensive to players of a different gender, race, sexual orientation or other group than you are. Again, you're in a public social setting. Show the same respect for whoever else might be there as you'd like shown to yourself, and don't assume it's acceptable to conduct yourself like the lowest common denominator.
DON'T barge into other channels where players may be focused on their own events. If you do pop in, listen carefully first to make sure you're not interrupting.
DON'T speak over other people. Even if someone is giving inaccurate information, wait until they're finished before chiming in. Chances are, the raid leader or other savvy player will clear up the confusion.
DON'T indulge in rude humor (burping into the mic, lewd remarks). This is still a public place -- show some class!
DON'T expect everyone to wait while you try to resolve any voice chat technical difficulties. If you are participating in a group or raid and your voice equipment or software isn't working, you are responsible for getting them fixed in a timely manner. If a simple reboot doesn't work, opt out of the event so that you can fix things without making everyone else wait.
DON'T talk over raid leaders, tanks and healers coordinating pulls, heals and cooldowns.
DON'T announce your death. Your healers and raid leader all know what happened. Unless you're handling a task in the raid that absolutely must be picked up immediately by another player, keep your announcement to yourself and let your teammates stay focused.
From <http://www.engadget.com/2014/01/06/drama-mamas-voice-communication-etiquette-for-mmo-players/>