This model is supposed to drain < 0.4W when in standby (IR only) mode. Which likely means that transient contents in all other circuitry, incl. DRAM and processor caches, are lost when it is powered off but still plugged into the power outlet. So, it is puzzling why
@Replicant 7 was able to "fix the problem" by unplugging the unit from the power outlet. This sounds more like a static charge buildup issue, which affected input ports, esp. HDMI.
In my A6A even with the latest firmware, I keep experiencing a ~10-15 second delay before the sound is played via HDMI ARC when switching between series episodes in the same streaming app, or between apps or OTA channels. I thought it might be a problem with my Samsung TV (a 4k QLED 950D model from 2017), but other users on this forum reported a similar problem with other TVs. So, I conclude this is an issue with this AVR. Given Yamaha's history of not providing a proper firmware update for many months now, I am inclined to return it to the store (a week left). I do not want to be stuck with a model that cannot correctly support the enhanced 4k refresh rates or 8k (when I buy the next TV) in the future.