If it is ok in the morning or early afternoon and slow in the evenings and weekends it could be an overloaded CMTS blade, if it's slow all the time it could be your equipment, noise in the system or a return signal problem. Try another computer that is proven to get the right speeds to eliminate your equipment, or deal with the slower speed and take the credit.That's a hard one to troubleshoot from here.
Never argue with an idiot, they will drag you down to their level and beat you with experience. Winston Churchill
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