T8s aux output causing feedback in monitors

Hey there,


I am using my T8s in a band setup with the following:


Channel 1-4 Vox

channel 5 elec guitar through pedal board 

channel 6 keys summed mono trs jack

channel 7 & 8 backing track from iPad via x 2 1/4 inch jack input


We are using 2 stage monitors from aux 1 and 2 outputs with separate monitor mixes via trs - trs jack


When playing at full volume we are experiencing what I believe is feedback, but feedback that sounds like an electrical interference noise.


Is the only way of adjusting the aux output levels by going in to each individual channel, or is there a way of adjusting the aux output? The prefs menu shows the aux output level, but doesn’t appear to have any way of controlling it.


Going through various different gain staging options doesn’t appear to help. 

The only thing that seems to help a little is turning the aux level right down on each individual channel, and then turning the floor monitors right up…but that doesn’t leave any head room for tweaking. 

I’m blowing my vocal cords out on a regular basis due to not being able to get enough in the monitor for fear of everything feeding back.


Can anyone please help me? TIA



Bose product name




What devices were you using that were affected and what version are they on

T8s going out to FoH Yamaha dx12 active subs & active DXR8s

aux 1 & 2 custom mixes to x 2  dbr12 active monitors