The solution involves purchasing a 2 line mixer. The input are the channels of VFO-A and VFO-B which are streaming simultaneously. The output goes to a Bravo headset amplifier which amplifies both signals. The inputs can also be balanced with gain controls on the mixer, Furthermore you can adjust the EQ on both signals for better inteligibility. When the chasers gets too loud I just move the slider to squelch down the audio from that VFO. Once I home in on where I think the DX is listening, I just leave the chasers squelched down and concentrate on the DX audio. This way I can hear him clearly when he answers me. While searching for the QSX frequency, I up the volume of the chasers to hear clearly which station answers the DX.