Thanks for your reply. Yes, I did a pass through on that reslotuion. My TV is 4k, but it is an RCA (non hdr, if that matters), which this x3, 4,5 didn’t work, as you mentioned that could happen.
I will go back to my OSSc and checking those resolutions you mentioned. Maybe I can find out how to get those Lx3, 4,5 if possible.