The Problem of Acting in AD

I just finished listening to Twin Stars from Kung Fu Action Theatre (another Canadian production from the look of the "re" and the lack of Brit accents) and Giant Gnome Productions with their fan audio Star Trek-Outpost and I'm reminded of the problems with using amateur actors in audio drama.
It may sound like a cliche but it still fits: Acting is about not sounding like you're acting.
If you have volunteers who feel confident enough to place voice to microphone to record- especially if they are not in the same location as you are- you might want to work with them on sounding natural. There are two very unnatural sounding actors that seem to still be used in audio dramas today:
1. The Reader is the kind of actor who is used to very carefully measuring the tone of their voice and speaking so very clearly that they are able to emote just enough to get you relaxed and have you thinking about the next audio book you want to listen to in the car. But they are not acting. The reader is so focused on the way their voice comes across so that everyone can understand the message they are saying, that they nearly always sound like a futuristic android given human sentiment through technological means. As narrators these actors are superb, because they have just enough emotion of a Lake Wobegon story and yet sound completely unreal when matched up with other actors. Especially The Emoter.
2. The Emoter is the kind of actor who swings wildly from emotional extremes. In a single scene they can inexplicably scream, act sexy, cry, get bored, and go back to screaming at an unbelievable pace.
While there are crazy characters that may call for such quixotic moods, most of the Emoters have forgotten that they are creating a real person and focus strictly on the emotional content of a line.
Even if a line calls for shouting, take it back to the writer or producer and ask exactly what range of emotions are required. Make them aware that going too far may make the character appear somewhat unbalanced.

So PLEASE, because someone can do a good voice or create an interesting character in an audition, doesn't mean they can sustain it. Make sure they do that, and you've got a winning team that will take you far.