Best way to scale output volume vs other parameters

So in my patch, as I lower the playback speed of groove~ I'm increasing distortion/noise/clicks to simulate a circuit I use. I have the sound where I'm pretty happy with it, but the volume goes up appreciably with the increase in distortion/noise.

I tried using scale, but the curve doesn't seem suitable. I tried using [expr pow] and adding a curve factor to the scale object, but none of it seemed to give me suitable results. I'm scaling weird values which isn't helping I think.

Any help and/or object suggestions appreciated.

Here is the patch:

(speed control control is top left, load buffer (or record) bottom right and the subpatcher controlling the noise is just above the output slider)