You said you fixed it with "vc4.inval_delay=0 vc4.cec_debug=0x100".
Have you fixed it with "vc4.inval_delay=<some number> vc4.cec_debug=0"
If not, there's no point adding a gui option to adjust the delay for you.
Ah, apologies, I naively assumed vc4.cec_debug adds some verbose logs to help debug problems or something like that. Did not realize it can actually affect anything.
The results when adding to the end of the "/flash/cmdline.txt" file:
TV does not switch on.
TV switches on as long as I send CECActivateSource within 3 seconds. Does not switch on if I wait longer (e.g. 5-7seconds).
TV switches on as long as I send CECActivateSource within 5 seconds. Does not switch on if I wait longer (e.g. 10seconds).
TV always switches on when I send CECActivateSource.
Then my question is, what does vc4.cec_debug=0x100 do and why does it fix my case? Is it something that can be added in the options instead of delay? Or is there a way to fix whatever that is affecting me? I'm happy to try anything else if it helps.