I've been monitoring this site for some time (it's great!). However, one question prevails.

I have a Sony AV3000, which has been set on the AMP button for device code 1058. I later found out that Sony AV Receivers are better represented by 4000 or 4001. The problem: None of the labels (MODE, SFIELD, CENTER+, etc. ) for DA4ES work using 1058. I can't add the new device code until the original is deleted, and this can't be figured out. There's a thread here for System Buttons and for labels, but these directions don't seem to apply to the device buttons.

Did Sony build in the correct codes for these labels? Do I have to resort to JP1 to activate them? Please advise. Thanks in advance. Any help with any of this is appreciated.

you have to delete any learned commands before you can enter in a new code. Once you do that you still wont get control of the sound fields, you will have to learn them from the original remote.

CB1

Code 1058, is a UEI remote code for Sony receivers, has nothing to do with the av-3000. Nor does JP1. Your getting your remotes mixed up.

OK, but how do I delete from a hard (and round) button. I can delete from everything else?

You cannot change a device code if there are any learned commands. You have to first delete all learned commands (clear the device), before you can assign a new device code. The first digit of the code number determines the device, so it is automatically set when you assign the code, regardless of which button or label it is on. There is no device code that has all of the functions for every component. This would be virtually impossible, but that is why this is a learning remote.

To clear the component of all learned commands (page 15 of the manual is wrong where it says "Notes on keys, etc”.
Commander off/muting
Set
Reset
Compo
Press component key or label
Yes

If you are talking about deleting a learned command from a hard round component key button:
Commander off/muting
Press "Learn" key
Press DEL/hard round button