A new modem was installed today - version 2B to replaced an original one from almost 12 months back.
The problem is worse - every 45 minutes there are two spike a couple of minutes apart ! And speedtests are lower.
The modem feels warmer than the old - so I checked heatsink temperature - old was 55oc and the new is up at just over 60oc!
Another call to BT tomorrow!
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M H C
taurus excreta cerebrum vincit