Need help recording Vinyl

Hey, Rookie here. I downloaded audacity today to record vinyl. I have an RCA cable from my the out sockets of my amp to the line plug on my macbookpro. When I click record nothing happens. In the preferences under recording device I tried both “built in mic” and “built in input” but no results. Any suggestions for a beginner are MUCH appreciated. THX

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I would personally have posted this in the Mac section of the forum and I would have found you yesterday.

If you set everything to record the built-in microphone, does it?

Reassign recording to the Mac line input and press record (turn the input source volume up). Pull the RCAs out of the amplifier, hold the two plastic bodies with one hand and touch the center pin of one RCA with a finger. Do you get bouncing Audacity lights and a blue waveform (and a buzz if you’re listening)?

If all that is true, you have nothing coming out of your amplifier.

Koz