bleed thru

hello…Im using Audacity 2.4.2 windows 10 64 bit Zedi 8 mixer..Im getting bleed thru when I overdub…mic disconnected gain all the way down…i still get a significant piece of the original recording in the new track…what should I do ?
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You need to work out where the bleed through is occurring.
Try turning down each channel of the mixer to zero, one at a time. Does the bleed through stop?

It doesnt seem to make a difference...I can turn everything down all the way...physically disconnect the mic and its still there…it only goes away if I turn the main mix all the way down at which point it does go away as does the sound of the original track…it still plays but no sound coming out of the speakers which is what it`s supposed to do

Where are you doing that? On the mixer or in Audacity or in the Windows sound controls?

On the mixer…assuming all inputs are disconnected levels turned all the way down no on line static just the computer playing an Audacity track back through the mixer into the speakers…there is a knob labeled mix that controls the volume…there is also a slider labeled main mix…both gains need to be turned up to hear anything…not all the way but there is no sound if both of these controls are off…usually I set the slider on 0db and adjust the volume with the smaller knob…as soon as I turn the volume up I get bleed thru.
There are buttons on the mixer that I`m not sure what they are for but for the most part if I leave them alone it works…adjusting them doesn’t seem to help .

The manual is not very clear, but the answer probably lies in sections 5.1 and 5.2 of the ZEDi-8 user guide:

Those are the buttons i was referring to…Ive read the manual frontwards and back...these sections make no sense to me..different combinations will cut the audio out completely or on only one channel..the only thing Ive been able to do is to try different combinations but nothing`s working.

There’s a couple of links here regarding Allen & Heath technical support:

My take on this is the USB “Mix” control is not turned all the way down.

I would be interested to hear what A & H had to say…