Can't import cds into iTunes

I can't import cds into iTunes anymore. Yesterday it was fine, but today I get this message "error occurred when converting the file (name of song). An unknown error occurred (3201)". I've been using an external USB CD superdrive to an external HD. I'm using Mojave and everything is up to date.

I moved the CD unit with its cable to a PC, and imported into iTunes with no problem. IU checked iTunes' configuration on both machines and it is identical.

I'm using a CalDigit dock with the MacBook Air.