I know most people say to turn off the avc on the rushmores but I really like that feature. If you tune the amp with the bike off, hooked to a charger, isn't that the same output as running with the avc on 4?

 

No depending on the amp in use some change as the power input voltage increases from running and aux position so does the audio output voltage change
the avc is activated by the wheel speed sensor.
I did do some testing this past spring and the voltage output jumps very aggressively depending on what stage you have the AVC set on 1 thru 4

 

Leave it off, and train your thumb to work the volume ****.