Thanks for the reply.
Yes, the RUT955 is connected to origin network via wire. The client experiences the slow speeds through either LAN or WiFi. I am measuring speed in minutes it takes to load google search and search for a speedtest. When connected via WiFi the RUT955 Web GUI appears to be affected by this issue as well, making it impossible to use it.
The same client connected to the origin network has network speeds according to telco contract.