Check the MTU setting in the router is correct for your ISP.
It is in the WAN setup menu on the left hand side after you have accessed the router.
For most ISPs it is 1480 but if you're with AOL set it to 1400.
Surface Pro (2017) vs Surface Pro 4
20 groundbreaking 3D animation technologies coming to Siggraph 2017
iPad Pro 12.9 vs Surface Pro 5
Synology invites you to visit them at Insomnia on 26th – 29th August. Book your tickets now and visit Synology.