So after searching, I'm still having trouble getting my MP3 player to work on my D3. I hooked the cable up correctly, and tried putting AV1 to EXT and/or Video. With Video, I just get a blank screen, no music. With EXT, it doesnt even allow me to push the AV1 button on the screen, its de-activated. Can someone tell me what I'm doing wrong?

Thanks!

Which connection are you using? If you are using the RCA connections behind the D3, you should be able to hear your mp3 player through AV1. I'm guessing that you are trying to use the mini jack in the front. In that case, you would hear your mp3 player through AV2.

sorry for the extreme late reply. anyhow, that worked well for a while, until my car was broken into. they tried to get the D3 out, with no luck. everything on the head unit seems to work fine, except for the AV2 input now. I cant get it to work at all. Can anyone tell me what the settings should be?

Make sure it's enabled in the setup menu.

It can only be set to video on AV2, correct? If so, thats what its set on.