Yeah, I agree with synergy's assessment. At this point, you might want to be looking for card/driver problems. Sure, you can saturate the hub with internet applications, but I'll bet they're running error-correcting protocols that are more solid and more tolerant of lost packets.

(Agreed that if this is the case, then Emplode should be more tolerant as well, but I'm just trying to solve your immediate problem here.)

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Tony Fabris