audio trim level setting
 

When setting my audio on the Z1 for XLR mic, I see that I can select a trim level from -18db - +12db in the audio submenu. I'm using a wireless lav and and a cam mounted shotgun. Any suggestions or guidelines for determining what trim level is suitable?

I have the limiter set to "on". On the outside of the camera I will be setting it to auto (possibly might switch the shotgun to manual and raise the level on the outside button if it's low, which it tends to be sometimes). How about the trim settings?