As mentioned in my previous post I used to see all these reported problems but since upgrading the cables and power off all devices I don't have the problem either when I first switch on all devices from standby or when switching devices. On latest firmware now which has fixed some problems I had with Satellite Sky SD channels (no sound) and iPlayer downloads from Sky (no sound from 2 channel stereo). So all good for the moment but it's no comfort for you all I know. The big change I found was powering off all devices simultaneously and then back on after new cables were fitted.

861v8, UHD722v2, 5200s, 5200HCSEup, M6s, 3200s, DSW, Sony 55A95L, Oppo 203, Sky Q Silver
Samsung QE43Q65B, Oppo 105 & Sky Q Mini