I was Prez of our local (fire company) Ladies Auxiliary for more years than I can remember. We always had a couple of consistent 'problem children'. It was a known fact that our social time was post meeting. We didn't typically have outside speakers but either board members or general members discussing an issue. When the side conversations would get out of hand I would simply speak over everyone and say 'Ladies...no one can hear what is being said by X. Everyone will have an opportunity to voice their viewpoint before the subject is closed'. It usually got the message across. I also, always made it a point that EVERYONE's voice was heard. But you also need to keep the conversations on track. When you get the inevitable members who have a tendancy to 'wander' when they speak, bring them back to the topic at hand with a gentle reminder that the points they have just made are the subject for a different discussion. Good luck with you new post. Having sort of walked in your shoes....