Whilst investigating possible reasons why our internet seems less than brilliant at the times, I have noticed that the modem is reporting FEC errors rising and falling in a regular pattern of approx. 1.5 hours of ~2000 FEC errors per min, followed by 0.5 hours of ~500 FEC errors per min. (See FEC graphs attached)
I assume it is interference from something local, but can't think what would be so regular. It must be on a timer, but what might be on for 1.5 hours then off for 0.5h and doing this 24h per day?
Superimposed on this is a longer period variation over each day. The 2nd FEC graph is a smaller scale, and there's definitely a 24-hour change rising and falling each day - getting more pronounced in the last 3 days.
Lastly, the bitswap graph shows this increasing at pretty much exactly 8pm each night and staying high for most of the night before returning to the low figure each daytime.
Might all these be caused by the same interference source? Could this be why our internet is sluggish?
Cheers for any ideas!
(Zyxel VMG1312-B10A modem bridged to Asus RT-AC68U router. BT ISP)