This happens about every couple of months. My speeds are normaly about 950mbps however it drops to the 300-500 range about every 2-3 months sometime more often. It stays there till I call support they go thru their routine and say everyting is fine but the speeds are still crapy. so they then want to send a tech out which they want to charge for if they find it is on my end. Now to clue you in I switched to a netgear modem CM1150V modem and Netgear X8 Router to get ride of the poor wifi with their X1 router I get 2100mbs wifi with it on both the 5ghz bands and 1000mbps on the 2.4 band with my netgear equipment. They had a fit and are always trying to get me to go back to their X1 which i have tryed several times with poor results.
anyway AGAIN my speed is down in the 377.59 speed "last test" my responce on the web is very slow. I wish there was a simple e-mail to support I could send the error logs from my modem to so they would fix it without sending out a tech who will again blame my system which is capable of far more than 1gig. "10gig" cat7 hardwired they will say everything is fine on their end and try to charge me again funny thing is a hour or so after they leave speed comes back.