Same here. Just set up a 85”Q70T with a
Denon AVR-X4200W. Wasted hours on this changing every setting one by one on amp and TV. I have used this amp on a Sony and a recently prematurely expired LG Oled (hence went Samsung this time ), up to now with no issues previously. Software updated on TV and amp. Exactly the same as JKJohns post . I have to use the Samsung remote to select “receiver HDMI” in sound settings every time the TV sis powered on; this will then switch the amp on . All powers off fine. Also phantomly powers up a PS5 connected to the amp at random and I have turned HDMI control “off” on the PS5! I have exhausted everything. Swapped cables checked and rechecked and retried all settings. Did you have any joy JKJohn? It must be a signalling problem on the TV. Source switching volume and power off all work fine, just the power on. Too confusing for the family so if I am not there they will be using the inbuilt speakers. I thought all HDMI devices used common protocolols? Obviously not Samsung?
