You may succeed with giving the kmsgrab system admin capabilities, it does no longer require explicit sudo then.

sudo setcap cap_sys_admin+ep /path/to/kmsgrab

https://linux.die.net/man/8/setcap
https://linux.die.net/man/3/cap_from_text
https://man7.org/linux/man-pages/man7/capabilities.7.html

I did not debug to the end, but I strongly assume at some point DRM hits this method, which bails out with -EACCES ("Operation not permitted") when privileges are not met.

@de_jean125 Something like that, yes. :)

My first guess was that it was for your kid(s), by the way.

You could even let it get nastier … "Stop or I'll hack into your bank account and send all of your money to homes for retired game programmers!"

@headrush69 Thank you sssssssssssssooooooooooooooooooo much headrush!
I have spent the last 2 days digging for this!!
My volume knob, It WORKS!

I literally created an account here just to thank you!

@rbaker The kit from adafruit comes with a boost converter that converts the 3.7V up to 5V.