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Anandtech review mentions built-in speaker starting squealing constantly, which is remedied only by power cycle.

Not constantly, it would only occur when he stress tested the machine. There also was a confusing statement to the effect that it only occurred if the machine was muted, but you could hear it only when you un-muted, or something to that effect.
 
Actually the internal speaker sounded pretty good compared to the one in the cheese grater. But, I use external speakers and not long enough to noticed any squealing.
 
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