If this problem continues with multiple devices, I would say it is either a hardware issue or ISP issue. I would call them up for a service call.
EDIT: I misread a little; you didn't say anything about trying with other devices.
I would try to hardwire other devices (computers or laptops) or get on the wi-fi with mobile devices and do speed-tests to check if these issues are also present on these devices.
As I stated on the last line I did hook up another computer to the FIOS router and it is not having the problem so it is not the FIOS but is a hardware issue.