Denali won't start after short time with key off but radio/ and or interior lights left on

[Big Mama]

One thing I forgot and didn’t see. The radio has two options for staying on. If you turn off ignition it stops when door opens. If you leave key in acc the radio doesn’t have a time limit that I know of other than voltage dropping then it turns itself off. I think you mentioned leaving radio on while getting gas. If it turned off low voltage not time was why? Fellas is that correct?