I've run some remote test and was not able to detect any fault on the copper network.
I can see that your modem is getting a sync speed of 11.5 Mbps Downstream and 1.02 Mbps Upstream, which is good based on the cable distance from your premises to the server. Your modem has been connected for almost a Month now, I'll refresh your connection to give a fresh start. You may turn Off the modem for 30 secs then On to give it a quick rest as well.
Check your connection and keep us posted if it's back to normal or if it's still slow.