No make or model... I built it
All the details are in my profile or under "My System" underneath my avatar. I've not heard the noise since I unplugged the card reader, so I'm assuming that was it. What would make a card reader do that though? The only USB port available is the one it's on, which is actually a hub... Too many devices lol. Never removed anything, which was why the disconnect noise was confusing me. If I don't hear the noise again I'll just assume my card reader is faulty (it's old and cheap).