Talkback button amplifies vocalist and backing track

Hi all

I use the control room a lot however, when i press the talkback button the vocalist can hear my talkback microphone, but they also get an amplified signal back from their mic and the backing track. I thought that if I pressed the talkback button it was meant to mute the backing track and let me hear the vocalist at the same level. instead the backing track audio gets doubled in volume and the vocal mic is very loud. both myself and the vocalist have headphones on , i ma using a shure mic in the control room to talk to the vocalist and they reply via the soundbooth mic which is enabled on the track.

I have mic 3 set up as talkback mic in control room, mic 1 is vocalist mic on the cubase mixer. i have a cue mix set up for the vocalist who can hear either the full mix or the tracks i send via cue channel, so all that seems to work fine. im on a focusrite 18i20 gen 1 soundcard.

Any suggestions much appreciated.

What is your Talkback Dim level setting?
grafik