Hmm... The only 23 -> 9 analog cable I have is the NEC model, which is molded and rubberized, hence I can't open it to check for you. (It's one solid coated piece)
Here are the best pinouts I could find, though. It looks like your cable is using the wrong ground, perhaps. (digital ground - pin 13, instead of regular ground, pin 16-20) Not sure if this would affect color, though. (I suspect it SHOULDN'T, but then again, I'm far from an expert in my understanding of how video signals work.) You will probably want to check out what is happening at the 9pin end of your cable, as well!
9-pin Video connector Analog RGB
(used by C=1084, Magnavox, etc. monitors)
01 = Sync ground
02 = RGB ground
03 = Red Signal
04 = Green Signal
05 = Blue Signal
06 = no connection
07 = Composite Sync
08 = no connection
09 = no connection
23-pin AMIGA Video
01-02 = External Clock + enable (usually unused)
03 = Red Signal
04 = Green Signal
05 = Blue Signal
06-09 = Digital signals (usually unused)
10 = Composite Sync
11 = Horz. Sync
12 = Vertical Sync
13 = Digital Ground (don't ground unless using digital)
14 = Genlock overlay
15 = Clock output
16-20 = Ground
21-23 = power outputs (+5/+12v!) (don't ground!)