I've searched and am looking to transfer recorded mp3's to the hard drive on the Z1. The manual says to use a special type of CD. Not sure if I'm burning them correctly onto the CD or not. I'm also wondering if a DVD can be used to transfer music tracks to the hard drive? Thanks.

No it can't be done.

You can only encode CD audio from a regular Audio CD to the Z1's hard drive in AT3 format. You can make an audio cd out of MP3's and then let the Z1 re-encode the audio tracks to AT3 for play back in the library. But that's about it.

I'm also wondering if a DVD can be used to transfer music tracks to the hard drive? Thanks.

No, you can only use a CD-R/RW