So, you have got that model, just found this whilst looking it up:
"Introduced in January 2001, the Power Macintosh G4 (Digital Audio) was the successor to the Gigabit Ethernet model. The motherboard was bumped to a 133MHz bus, the AGP slot was increased to 4x, and an additional PCI slot was added, bringing the total number of PCI slots to four.
It was available with five different processor configurations: 466MHz, 533MHz, dual 533MHz, 667MHz, and 733MHz. A SuperDrive was now available as an optional component.
A noteworthy aspect of the Digital Audio model was the elimination of an analogue audio-in jack, forcing users to buy third-party hardware (most commonly USB-based) for audio input. However, it also contained a built-in amplifier for use with Apple Pro Speakers or a breakout box. "
Have the same problem with my ibook which I'd like to use to record records onto as it would mean not having to move my stereo next to the computer. I have found this device by griffin:
http://www.griffintechnology.com/products/imic2/index.php
Also includes a program to record the music onto your Mac 'Final Vinyl' which makes the price not too bad.
It's annoying when they don't put a stereo in socket on computers but then the USB connector is said to be better quality anyway.
neye: