Unknown mod for my AD20. Any help?

[redbook]

it is, but in my case, I really appreciate those supersexy knobs oh yeah

[rustoleum]

It is the standard unit PLUS the extra optical out.
So I can run it straight to the JB3 with a optical toslink

FYI - The extra output (the mini-xlr) is not an optical out... it's a coax spdif.

[cfbarlow]

How did you guys get the knobs on?  I've tried this before, but the knobs were never secured, so they spun and didn't change levels.  Which is totally pointless  

[bagtagsell]

i bought those same knobs.  never used them for anything, just waitin to scheme something up with them.