SD16/SD8 Inputs but no Output


Kicking myself for not registering within 90 days (or it would still be under the 3yr warranty) but just short of 2 years my SD16 has nothing coming out of the outputs. Power and AES50 light comes on without issue. Inputs all work just fine but no output. I'm sure it's not a config issure as I've tried everything under the sun. The mixer is definitely sending signal as I'm able to see it on the meter and replicate the output to a local bank of 8 outputs on the x32 mixer.

As the final troubleshooting attempt, I replaced a known working SD16 in a working setup with the one to troubleshoot, and sure enough, none of the 8 outputs on the SD16 were picking up anything. I've cracked the unit open, checked all the connections and did a quick inspection for any blown caps or damage but couldn't see anything. I then put it back together and had the same results. 

This thing was used for a few months initially with no issue, then sat in my basement as a backup for the better part of a year and a half until I was able to get another X32 to use it with. Any suggestions would be greatly appreciated.