Hey andrewe,
Thank you for reaching out! That is certainly very odd. Generally, for most fiber-fed buildings there is a 3rd party router that is included from us. Do you have any of the 3rd party routers listed here? If so, when you connect that to the fiber modem directly, are you getting 150 Mbps + with a direct ethernet connection to a PC? Keep me posted.
Cheers,
Tony | Community Mod.