I have a 16″ 2021 MacBook Pro, a cassette tape player, and a bunch of old cassette tapes with family audio recordings on them. I want to digitize them by connecting the tape player to my MBP's 1/8″ audio port. I have tried getting a regular male-to-male headphone cable, and the MBP (using GarageBand) does not detect any input.

What kind of adapter do I need to make the MBP recognize audio input from an 1/8″ audio cable? Does the headphone jack on this machine even support line in? If not, is there a USB-C adapter that will work?