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Hmm.... Not sure what to tell you. :(

I'd really try some new memory, since your memory is giving errors. Then, if that fails with new memory in those slots, I'd try Apple.
 
If you send your memory back and get new memory and they come packaged in pairs put the first two in lots 1&3 and the second pair in 2&4. Try not too mix them up because when they packaged in pairs they are matched pairs. Good Luck.
 
OWC = overpriced. Crucial is just as good, and costs less. Having said that, there are also other options such as Corsair, G.Skill, and others.
 
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