Mixdown track mysteriously compressed

My multitrack mixdown is fading my output track for some reason. I have simplified just to troubleshoot and it still does this. All I am doing now is this:

open  Audacity new session

create a new multitrack file (44100, 16BIT)

import a wav track (44100, 16BIT)

export multi-track mixdown wav (44100, 16BIT)

But the exported track waveform is visibly quieter. I have checked the faders everywhere in the mixer and the editor all at "+0"

Anyone?

using Audition 23.3.0.55 on a Windows 

AMD Ryzen 9 5950X 16-Core Processor 3.40 GHz

64-bit operating system, x64-based processor

Windows 10 Pro 21H2 build 19044.2965