sync is now the same as max attainable.
Looking a bit more at the stats it seems Quiet Line and Hlog changed slightly for the worse, especially at the higher tones.
When the engineer first arrived he seemed pretty sure that I should get 80/20. After "fixing" the fault and coming back to my house and with me telling him sync was worse than before, he said he would test what sync he could get, so he plugged in his tester then after a few mins gave some excuse that it (his tester) needed to be charged, nothing more he could do, goodbye.
It's almost like he'd realised why it was worse and could not wait go get out the house fast enough!