I catch myself doing that too!!! One thing that really helped me is that twice now, I've been directed by other podficcers: once in a theatripod project and once for an independent project. Both times, the directors insisted I remain with the characters, visualizing what was happening for them in the scene and committing to their experience (or connecting it with a similar one of my own), even if it's not a super dramatic moment.

Now I try to remind myself to do that. I also recognize that certain sections of narration actually are okay if read straightforwardly. Esp if you want a nice contrast with the more dramatic moments. How MUCH drama, and how MUCH straightforward reading depends on the podficcer's taste and the needs of the fic, I think. I tend to swing more subtly between moderately straightforward and moderately dramatic, but then again I'm a narrator at heart, not an actor. :)