Hi ! Same problem here.
Reading your post made me think of a simple thing : using a tuning app on your phone like the ones made for guitar player ?
Do you mean using Synth Sampler to grab a piece of voice, shorten it right up so it’s a tone, then tune it to C?
I used to sample bass tones into op and use the sampler to play the tones chromatically. I found sometimes (no mater what key I pressed to start sampling) my bass tone would sample at F, sometimes G and sometimes B seemed to be determined by how dense and noisy my tone coming in was. I had thought it sampled to a specific key (A?) but that wasn’t the case for me. I would just use a clip on guitar tuner mounted near my monitors and I was able to just keep resampling until my notes matched up ( I would check them against regular synth)
aight guys i diddnt know about that tuning-page, thanks a lot for your help, this should get me started