HELP!

First things first: I read the FAQ and the linked webpages BEFORE doing the upgrade. I want to upgrade my mk2 with a second harddisk (IBM DJSA-220).
When I gently disconnected the IDE cable from the factory installed 6Gb IBM drive, I noticed a loose wire sitting on the IDE cable. It looked as if it was in between a pin of the harddisk and the IDE connector itself. Did I do something wrong? I do have huge amount of PC assembly&repair knowledge (9 years now) so I know I haven't done anything wrong sofar. But I'm really puzzled about this wire... Does anyone have a clue regarding this strange black 4.6cm wire?
I also did send an email to support, but I hope someone can help me sooner, since the player is still lying here dissassembled.

Edwin de Vaan
mk2 rev.7 Trillian # 080000263 6Gb blue/red