The Wall Street Journal had a really funny article on conference calls a couple years ago, and from that I can extrapolate that one of the most important things when participating in a conference call is not to be on the toilet.
Some people do anything they feel like doing, because they think others can’t see them, but people can often tell when you’re on the toilet, especially if you flush during the conference call.
There are also people who put the conference call on hold while they go do something else, or when the meeting starts to get boring. This is a bad strategy if your phone system plays music while people are on hold. Suddenly the other people who are in on the call will hear music and know you’re not there.