We have two classic Studiolive 16.4.2 that are firewire linked together. They wokred fine for our last show about a month ago. For this show we suddenly are getting no sound out of the subgroups our or the aux outputs. I know all cables are in working order because if we unplug from the subs or AUX we plug the 1/4" cable end into the Main 1/4" out put we get sound. The meters are showing that the subs are sending sound, but nothing is coming out. All other features seem to be working. I even unlinked the two boards and ran them as a single board and we get the same problem on both boards. They are running 150a 190 on the firmware.