No sound coming out of twin L1 compacts with a external mixer

I have twin L1 compacts. I just recently got the second one, but the original one I've used for wedding ceremonies numerous times and I love it. My initial thought was to use both L1's with my external mixer. So I hooked up two 1/4-1/4 TRS cables, one going from the input of each L1 into the mixer. I've tried mono, I've tried stereo, and I can't get any kind of sound whatsoever. I just can't figure out what it is I'm missing. Any ideas or suggestions would be greatly appreciated!

Hi Bluebeard,

 

It would be helpful to have some info on the mixer.

 

Make, Model, link to operating manual, etc.

 

O..