display setting changed after power cycling hdmi monitor

[nitrohepcat]

after turning off the monitor overnight, when the monitor was powered back on the display settings somehow changed from the default 720 to a much higher resolution with lots of flickering

[Qengineering]

It's a known issue.
As soon as the HDMI powers up, it sends its resolution to the HDMI source, the Banana Pi in our case.
The Banana Pi sets its output to the newly received resolution. However, due to its limited RAM and its clock, the BPi isn't capable of refreshing the screen adequately. Hence the flickering.
Sure there is one setting preventing the BPi from changing its resolution even when the HDMI asks for it.
Unfortunately, I couldn't find it yet. If you have any ideas, please let me know.