using a SRAM Red PC-1091R chain. it has about 3000 miles on it.

it's developed some pronounced of squeaks and other noises - re-lubing makes them go away, but only for a few days. i feel like it should have held up better than this.

how are you lubing it?
I would soak it in lube so it works it way into the pins and not just to the out side it needs to get into the pins and soaking is best for this bubbles will come out for quite some time as it works it way into the pins.

I wasn't aware that 3,000 miles would have a significant impact on lube retention.

Is it stretched out? 3,000 miles seems like a lot for a chain?

Squeaking means lack of lubricant, not worn chain.
A properly lubed chain will not squeak, no matter how worn out it is.

3000 mi is a lot for a SRAM or Shimano chain. Measure it. It's likely it needs to be replaced.

Measure it and see. We can't tell how worn it is by a description of a sound over the internet.

so.. how often do you lube otherwise? I lube every ride or every other ride. Less than that, and things are bound to not work so well and wear out faster. I would expect a chain that hadn't been lubed in 3 or 4 rides to sound pretty squeaky.

Forget the lube for now. Measure it as suggested. If already stretched, you aren't doing your cassette any favors.

+1. Lubing and continuing to ride a worn chain is just silly and is gonna cost ya a complete drivetrain eventually. Just measure. Toss if stretched, or keep if good.

Throw the chain away. I don't know why people have such a hard time with "replace your chain after 1500-2000 miles", but it's a pretty simple concept. Chains are cheap, casettes and chainrings aren't.

Exactly, they aren't expensive either and pushing the life of your chain will not prolong the life of the drivetrain.

PC-1091R go for like $70 a pop

We CAN, if the sound is right.

A nice POP!, SNAP!, or BANG! followed by "Oh ****!", a scream, and then a WHUMP! followed by muffled moaning and whimpering can be definitive from a very long distance.