1999 Audi A4 (w/Bose)--Delphi install

We did one of these recently (fm modulated Sky-Fi) and the car no longer has AM reception, although the FM reception seems to be fine.  I tried using the amplified antenna adapter and that didn't really help much--it eliminated a TINY bit of static but you still can't hear any of the am stations.  I didn't really have a lof ot time to fiddle with everything but am really confused as to why the AM reception is so crappy.

A few months ago I had a similar problem with an aftermarket deck install in a  99 new beetle.  We initially did not use that amplified antenna adapter and the customer got poor fm reception and NO am reception, but once we used the correct adapter all receptions problems disappeared.  So that's why I was kind of hoping it would be that simple for this Audi, too.

If I understand it correctly, the only way to get the factory am booster to turn on (if one even exists in this Audi) is to have the amplified antenna adapter plugged directly into the factory antenna cable, rather than being plugged in to an modulator first or anything like that.  And of course the blue wire needs to get 12 volts.  But I am pretty sure this is how I had it connected when I was trying things out a few hours ago.

Anyone know what might be the problem? Thanks in advance.