Just an update....
2nd engineer visit - ran some checks, made a few changes and said he'd lowered downstream power levels and increased upstream to 36. After he left it DC again and I checked upstream levels and all at 31 or 32.
3rd engineer visit - replaced ONU and intinuator and again tweaked power levels.
However, signal is still disconnecting even though upstream are all 41 or 42
There seems to be a mountain of similar posts on here all with one thing in common - Hub 3
I am not relishing the prospect of phoning VM, its like Groundhog Day