I'm thinking that sounds about right "beat" for the serpentine belt. Perhaps a contaminated area or a slick spot on it.
The other thought is that hasn't quite made it to "chirp" yet. So I'd check for loose spark plugs as well as pull the dipstick to see if the sound goes away.
The other thought is that hasn't quite made it to "chirp" yet. So I'd check for loose spark plugs as well as pull the dipstick to see if the sound goes away.