After a great deal of frustration, I finally got the Phatbox to work properly with the RNS-E.
I searched the forums here and at phatnoise.com, but I didn't see anybody else in the world that had the same problems I was having. So, maybe this problem is only particular to me, in which case this post is here only to help me out in the future when I have this problem again for some reason...
First off, let me say that you won't get anywhere until you upgrade the phatbox firmware to the latest version for Audi (I think it's version 7.02 as of today).
Here are the problems I was having:
The first problem I had was that I couldn't get the phatbox to accept the fact that I was using the RNS-E. I got the Phatbox Radio Setup Guide from here:
http://www.phatnoise.com/audi/support.htm
And I was able to figure out that the RNS-E is referred to by the phatbox as "Radio Type T". So I go to the CD6 menu and then hit the > button until I get to Radio Type T (I think it was track 24). When I pressed the RNS-E control knob, it just said "Please read the Radio Setup Guide for more information". But what it was supposed to say was "Radio Type T selected". This turned out to be a big clue that something wasn't right.
But at first, I just ignored this little problem and went right ahead with using the phatbox. It mostly worked, but there were a few minor details...
When I hit SCAN, instead of getting all the ID3 tag info, all I got was the Playlist. Not very useful. But I learned to live without a SCAN button on my D-Navi (in my other car) so I figured I could learn to live without it in this car.
Next, when I tried to select an artist (CD4) I could scroll through the artists one-by-one by hitting the > or < buttons. But if I held down the < or > button it did NOT scroll through the alphabet ("A, B, C, D, ...") So if I was on, say, Led Zeppelin and I wanted to hear Aphex Twin, that meant I would have to hit the < button about 500 times. Not too good.
Finally, when I tried to put the phatbox into Random mode, it appeared to be non-functioning. You can go to CD Control, and you can hit "MIX", and it will say "CD MIX" at the top of the screen...but if you tried to skip to the next song, it was always just the next song in order of the playlist...never random.
Now the solutions:
***To get the phatbox to accept your selection of "Radio Type T", here's what you have to do:
1) Select CD6. This gets you to the feature menu. Duh.
2) Hit < or > to get to your radio type. In my case, it's the RNS-E which is Radio Type T (for my other car, it's the D-Navi which is Radio Type S) -- DO NOT press the Control Knob. This ALWAYS fails.
3) Quick! Now you have to hit the "CD Control" Control Button, and then rotate the Control Knob until you have "SCAN" selected. If you were fast enough, then the voice is still talking, telling you that this is "Radio Type T". NOW, press the Control Knob. This time, provided you were quick enough, the voice says "Radio Type T selected", and you know you've done it! If not, go back and try it again. It's really fun. Pretend it's a video game. Whee!
Now your SCAN button should work fine, and it should read off the entire ID3 tag, including Track Title (if you selected that option in the Phatnoise Music Manager).
***To scan through the alphabet when looking for an artist, you use a very similar trick:
1) Select CD4. This gets you to the Artist Selection menu. Duh.
2) Quick! Hit the "CD Control" control button. Now, rotate the Control Knob until either << or >> is selected. Now you can hold down the Control Knob, and the voice will say the letters of the alphabet, allowing you to quickly speed to the artist you want.
***To hear songs in random sequence, here's what you do:
1) Select a mode to be in (Playlist, Album, Artist, or Genre) using the appropriate CD#. Duh.
2) Now, go to CD Control. Select "MIX" and press the Control Knob.
3) Now, no more touching the Control Knob or < or > buttons!!! Seriously. If you rotate the Control Knob or press the < or > buttons, the MIX setting gets very shy and disappears. It should say "CD 1 MIX" at the top of the screen.
4) Now you can go and do your NAV or NAME tasks. You can look at the map, you can plan a route, you can enter names and addresses and phone numbers into your directory. You can do anything but touch the < or > buttons, and you'll be fine: the songs will play in random sequence.
So there you are. Now your phatbox has about 95% of the capability it had before (the only thing you can't do is skip to the next song while in random mode).