I certainly have never encountered what you have. Yes these fake search results do damage the numbers of real results but the only thing I have found that really seems too be related to your problem is from 2002
XXAA is watching, SPAMing the network, proof
Are you actually downloading these 134.4 files .. or are they downloading them selves? I would suspect a virus .. but on a mac????? I'm feeling a bit stumped right now I'm afraid.